The Falcon / CAA G27 on my Ar15 and Rem870... like it because I have long fingers. Places correctly my index on the trigger.
I also have the ERGO ambi suregrip on my 10/22. Also very nice, but not as deep as the G27. I prefer the softer rubber of the ERGO, than the solid composite of the G27.
But now, i want to try out the Magpul MIAD for my A15.