As far as plugging in for an hour and fully charging the batteries, no way, not unless they are 98% charged when you plug in.
While one could go from 50% to 80% rather quickly with a high amp charging source like a 60 amp converter or a well wired and capable alternator, 80 to 100% takes about 4 hours no matter how powerful the charging source might be. The higher the state of charge, the more resistant the battery becomes and the less current it can accept and charging slows greatly.
Regularly returning the battery to a true 100% is important for achieving good battery longevity.
Partial state of charge cycling is much harder on batteries, more so to AGM than it is to wet/flooded.
Any and all charging sources should be employed whenever possible to keep the batteries as close to 100% charged at all times. Anything less compromises their longevity to some degree.
At what point in time the capacity loss of the battery(s) becomes noticeable to the end user will range wildly. Many people will claim a battery bank to be just fine and performing just like new, and then one day the remaining capacity shrinks to the point it upsets the users habits, at which point it is no longer just fine. In reality the battery capacity is decreasing from cycle one. How fast it degrades is directly proportional to how well it is recharged and how deeply discharged it was.
AGM batteries tend to weigh more than their same sized flooded counterparts and tend to have slightly less capacity too. They have less resistance and tend to charge faster at all states of charge than flooded but how much so varies among brands.
AGM batteries tend to have higher resting voltages and will hold higher voltages under load, than their flooded counterparts, but this, in house battery duty, is only really important when one is running huge loads via an inverter. The higher voltage held does not make them magical, it is just a characteristic of them.
The least expensive AGM's are limited as to their maximum charging rate, no more than 30 amps per 100Ah of capacity, but they still enjoy rates up to this level. More expensive AGMS have no upper limits on charging amps as long as a certain voltage is not exceeded, but these batteries also require high amp recharging when deeply cycled, way more than solar can provide in most scenarios.
There is more than one way to skin this cat. Newbies tend to be battery murderers as they do not know how much they are actually depleting the battery and how little their charging sources are actually returning, to their punch drunk chronically undercharged battery. Solar is great as it produces at least something when it is daylight outside, and as that last 20% takes hours, well the solar can have the time to do so, silently.
Cleaning of the solar panels is hardly a dealbreaker. I often go months between busting out the squeegee on a long pole and output never seems to increase more than 15% once they heat back up.
if I had to set up a portable panel everyday, well that would suck, and my battery would be unhappy, packed up all its toys, and went to the recyclers long ago..
Figure a 12v 1.8 cubic foot compressor fridge alone, in a sunny environment, requiring at least 60 watts of solar to run indefinitely. Yes this number can be higher or lower depending on the many many variables which impact solar generation and fridge electrical consumption. With Solar, more is Always better.
I'd say to get a charge controller which allows expansion to 200 watts to 250 watts.
6v GC batteries are the most durable deep cycle flooded batteries available, no 12v flooded battery comes close.
AGMs blur the line between starting and deep cycle duties. I am suspicious of well priced internet AGM's. Asian AGM quality can be a crapshoot. These AGMS do not have the super low self discharge of higher quality AGM's. Add the slow boat ride from China then warehousing them until somebody clicks 'place order', and the battery could have self discharged below 80% and already be sulfated to some degree, before the user puts it into use, and saving 20% on a already sulfated battery is Not saving any money.
But I guess they could be sold soon after arriving and premature sulfation not be an issue and they might very well provide good service to the person who can recharge them promptly, fully, often.
One other thing to keep in mind is one can have way too much battery capacity and way too little solar. If Solar is to be the only recharging source, then 2+ watts per 1AH of capacity should be ratio one seeks. The deeper the level of discharge of the batteries, the more important it is to have a higher solar/capacity ratio.
With AGM's, 2 watts to 1AH of capacity, should be the minimum, especially if is is a higher quality AGM like Lifeline, Odyssey and northstar, but ideally these batteries would have a 4 to 1 ratio if cycled to 70% and solar was the only recharge method.
4 to 1 is unrealistic on most systems, so other charging sources should be eyed to occasionally fulfill the AGMs greedy needs, in that it occassionally requires being recharged at a high rate, from its most depleted state.
Many AGM's are tickled to death with too light of recharging currents, and 100 watts on a 125AH battery being the only recharging source, it definitely in the tickling zone.
How long the battery will live in such a scenario is really unknown. It might still yield acceptable lifespan to the user, or it might give up the ghost in 2.5 months, after which a true 100% recharge and recondition might be attempted to restore lost battery capacity. This means high recharge rates to a higher voltage and held for a long time until the amperage accepted at those higher than normal voltages tapers to 0.5% of battery capacity, at 77f.
Usually, hail mary attempts at restoring lost battery capacity are fruitless, or if successful, shortly lived, but this hail mary can also serve to allow the battery murderer to understand how to not repeat batterycide on their next battery. HOlding higher voltages for longer than normal to perform this hail mary/reconditioning/equalization charge usually requires special equipment to achieve. Having this equipment or at least meeting the battery minimum requirements in the first place, and used regularly, can easily triple the usable lifespan of a battery.
In the planning stages, one has the most flexibility and options, and building a balanced system now might cost a little more now, but cost less in the long run with batteries that might last significantly longer. Get a controller large enough to handle more wattage so you can buy another panel or 2 as you see how much battery capacity you really need, and how much recharging you need to keep that battery at least on the happier side of batterycide. If you are permanently mounting a panel on the roof, then use much fatter wire than a 100 watt panel alone requires, as running the fatter wire required for 2x the wattage later, costs more money and effort.
By all reports the wally world 29-dc gives adequate service when not cycled too deeply and recharged promptly, but I will personally never own another Lead acid flooded marine battery, and certainly not the wally world versions. Group 27/31 Trojan/Crown/Deka/USbattery are all superior to a wally world group29, cost 25% more at a minimum, will have 2x the cycle life in the same usage, but even these upper end Marine batteries have only half the expected cycle life as a pair of 6v golf cart batteries.
Any Yes Trojan scs 225, a group 31, will have 'deep cycle' printed in bold letters right on the side, but internally it resembles a starting battery more than it does a golf cart battery whose original design is all About Deep cycling service and resistance to abuse. All car jar batteries in the stanbdard group sizes were designed as starting batteries, for maximum CCA numbers. Later on they tried to stufff 'deep cycle' plates/ internals into them, and they are simply compromised in this duty and have limited success in getting the Lead/acid ratio correct.
Golf cart batteries will also tend to require less time at higher voltages to reach a true 100% charge( easier to fully recharge), and if accidently overdischarged, stand a much better chance of returning to within a small percentage of their capacity before the incident, when properly recharged. A marine battery might just say screw you when discharged below 10.5 volts and left there for a few days, or if it does recover, will have lost more of its remaining capacity from the incident and will require more time at higher voltages from then on out to reach a true 100% charged state. If they do not get this extra time, then they degrade that much faster from that point.
This is often why many starting batteries fail soon after that first jumpstart was required, even on the battery that was not very old when the interior light was left on overnight to require the jumpstart. MOst if the time starting batteries fail simply because the general public thinks an alternator can fully recharge a battery in 15 minutes, instead of the 5+ hours it will take.