I think both are good choices. We used wool, but I know a lot of people that use thinsulate and are happy with it. A lot of people I see add some sound deadening stuff to the walls before insulating. We choose the wool as it’s supposed to generate heat when wet. My thought there was it would help dissipate it as we choose not to build a vapor barrier. With a fan we’re pretty comfortable right now. It’s around 100ºF out at the moment. In the winter we were pretty comfortable with a heater. If you have a ton of windows it probably won’t matter either way. We did notice a pretty large reduction in sound with the wool. It’s supposed to be good for that. If you look at the havelock site they have a whole page dedicated on why to use it for vans over the other options. Havelock Wool - Healthy, High-Performance Van Insulation. Overall we’re happy with it, but I think the wool is probably more work than the other options as well. We basically sewed ours in until we added framing and walls to hold it there.