Which solar panel to buy

[the evil twin]

snip...
As for the reg my 80 watt panel had one glued to the back it cooked the internals.

Yep the best environment for a Reg is a cool dry place, the hotter they get the worse they perform...
The best location electrically is close to the Battery so the cable losses are not on the output side which is bad for the Batteries

So where do the Ebay muppets glue them?
On the back of the panels... and then most of 'em throw in a 5 metre cable or more with an Anderson on the end 'for your convenient connection'

Total 'tards the lot of 'em