The Zamp panels are indeed pricey, but as the solar connection on our (2016 23MRB TT) says to use Zamp, we decided to err on the side of caution and go with that. We ordered the 160 watt, as that's what the Zamp site recommends for the battery we have. We liked the features: carry bag, legs, easy-to-see info panel, and, of course, state-of-the-art solar tech.
The unit we ordered has shipped, but we don't have it yet. We look forward to a) it taking up less room to pack, b) not having to open the battery case and alligator-clip the solar directly to the battery, and c) not having to find things to prop the panel up on. We're fairly handy, but not with electrical stuff, so ....
We'll see how it works on our first trip with it, scheduled for the end of this month. We too like shady spaces, but these are supposed to work even in filtered light - even in moonlight!