A very subtle point but possibly unnoticed.... There are quite a few panels now being sold as "semi-flexible" which, in marketing terms, appears to mean that they are rigid panels without the aluminum frame. One must figure out a way to mount them "rigidly" so they don't flex (much) and have enough space around them for adequate cooling. Everyone's setup is different but for mine, that would add a lot of complexity/work to the installation. Just a heads up to look closely at what one is buying. :-)