Oh... do you by any chance know which is said to be better? How did you like your experience at ME... other than no balconies?
ME is a really really nice hotel. Probably one of my favorites and I've probably stayed at 100+ hotels. I don't know anything about Gran Melia though since I've never even step in it. Check out tripadvisor.com, it's filled with reviews from people who have stayed at the hotels.