Personally I'm a fan of both, although I'm more versed in real robo having watched a lot of gundam and some macross movies. I'd say on the fun scale, super robot is all about that goofiness that defines anime while real robo has some good stories to tell and mechanical designs that wow you.
Mazinger was one of my earliest exposures to mecha, and rocket punches (and rocket boobs) were awesome all the way back then.