I loved Giant Robo because there was very little fanservice. Seems like a weird reason to like it (it had other good, no, outstanding qualities as well) but something about a show being aimed at a general audience and not ronery otaku really spoke to me.
What little fanservice we did have - Ginrei and her fantastic legs - was very mild but still oh so hot.
I'm hesitant to watch the Ginrei special because I'm afraid it'll shatter my all-ages experience with the OVA.>>10037229
It's better than Gurren-Lagann. Much better. Not as funny and the main character Daisaku doesn't go GAR even once, but it's an amazing, tear-jerking, fist clenching, heaven raising epic.