dear matt i have owned a gt750 1988 E reg for about 2 years it has got 31000 miles on and i have not had a bit of trouble out of it as to your question about swaping a cx500 for a gt750 be aware as i suspect your friend is that they are not popular and they dont go for big money i think its because of the weight 220kg it does put a few people off but they do have good pulling power and they are reliable check under the tank rims for serious rust and that the flimsey horn switch work as you will stuggle to find a second hand one that works