This, this and this... I HATED G.I. Joe (and the Transformers for that matter) back in their TV heyday.. Robotech was my cartoon of choice because people died, ran through a gamit of emotion and had to deal with everyday life. Joe was just too clean and neat and everyone survived..
As for the Transformers, I really just didn't like the animation (and still don't).
I'm assuming I'm younger (born in '77) I've never heard of Robotech.
I'm not sure how much of G.I.Joe was shown in the UK (where it was renamed Action Force)
I still have plenty of time for Transformers though.
Yes, you're a bit young to remember Robotech the first time around. Long story short... In the states, Robotech was a mash up of three separate Japanese Anime series that started showing around '83 or '84 IIRC.. The three series were shown as Robotech: Macross Saga, Robotech Masters and Robotech The New Generation. They basically dealt with Earth's first foray into space after an ship crashes here and then the subsequent invasions of other alien races trying to get at the energy source for the ship (this is all highly paraphrased from memory, you understand).
The animation was very, very good (IMHO) and the storylines were compelling. The show wasn't originally intended for children in Japan, so deaths of major characters are shown. There have been subsequent attempts to create original sequel material over the years, but most of them have been pretty dismal. The show itself retains a strong following and a live action movie starring Tobey Maguire has been in various stages of development hell for a couple of years.