I like the folding canvas case type portable solar panels. Much more compact than the typical "solar suitcase" (2 rigid panels with a hinge) like the the 100 watt model that Renogy offers. I carry these in a 4wd for camping and exploring in the back country to maintain the starting battery which is also powering a 12 volt refrigerator.
Currently I own a GrapeSolar 100 watt folding solar panel (unfortunately no longer available
), a RockPals folding 100 watt panel, and a Baesan brand 80 watt folding panel. I have recently ordered an Itehil brand 100 folding panel for testing.
The GrapeSolar folding panel has so far been the best unit (cost the most as well, at about $300.) Basically 5 x 20 watt monocrystal panels sewn into canvas folder with a pocket for cords, etc. Very compact and lightweight, with quality construction and good power production. I have owned this panel for 4 years.
The RockPals 100 watt folding panel I was able to purchase on a super sale 1.5 years ago for around $140. Similar to the GrapeSolar model in concept but different in execution. 4 x 25 watt monocrystal panels sewn into a canvas folder with a pocket for cords. Larger in dimensions and heavier in weight than the GrapeSolar unit, but the Construction quality is okay and electrical production is good.
The Baesan 80 watt panel I purchased in April 2021 and while the price was right ($85 on Amazon!) it has been a big disappointment. Electrical production was very poor, like 30 watts mid-day in full sunshine. Construction was okay, but it is really designed for recharging someone's cell phone or tablet not an automotive or house battery.