I have 3M, Meguiar's, Flex, and Lake Country.
I actually like them all but one thing I prefer is they be somewhat flexible. A backing plate must be rigid enough to properly support the pad but also soft enough to follow the contours of the panel.
While I listed the Flex above I haven't tried it out yet but it does look very promising. I'm intrigued by the flexible foam layer and this could be my new favorite pad.