I prefer a few of the Showa films over the Kaneko stuff. Yeah, yeah, yeah...just shut up.
Here's my list, in terms of favorites...
Gamera vs Guiron
Gamera vs Gyaos
Gamera vs Jiger
Gamera 2
Gamera, Guardian of the Universe
Gamera vs Barugon
Gamera Supermonster
Gamera 3
Gamera vs Zigra
Gamera vs Viras
Gamera, the Giant Monster
Gamera, the Brave