>>7480124I have owned most of these.
Might Gaine is awesome, really solid and imposing. It took me a while to discover that you could pop his feet downward to get better ankle articulation, and the fin on his shin moves along with it. So cool.
GaoGaiGar looks great, but is very heavy, which makes him sort of unweildy to pose. He is capable of posing well though, you just might have to struggle a bit to get him there. He becomes even more unwieldy once you add the Stealthgao II, Goldymarg, the Goldion Hammer, Dividing Driver, etc. but man, does it make for a magnificent display. Be sure to get the wind effect part if you still can, it looks great too.
I never owned any of the Getters, but did hear good things.
The Mazingers are pretty basic, but still very solid figures. Hip mobility is a little limited by design but otherwise they're very well articulated. Goes without saying that they look beautiful, super glossy finishes.
To be honest, I've never really had a bad experience with the SRC line. I'd highly recommend it. Give Gurren Lagann a shot too if you're into that series, you get over the big kneepads very quickly in person, and I still think it's one of the best toys I own.