Ive driven both. They are both very nice, however, if it was me I would buy a 5.0 and add mods to it. Save some money! On the other hand if money is no object then go for the GT500, it will probably have better resale value down the line and having a 5.4 wont hurt either. I have the 2010 and wanted the 5.0 I just couldn't fine a used automatic, I'm done shifting, to hard to eat when driving if you have to shift! I also didn't want to pay retail for a new 5.0, Id rather get it with 10k or less and save some money. I might go for a 5.0 down the line but I'm not in any hurry, it has to make sense and the deal has to be there for me to pull the trigger. My 2010 is fast enough to get me plenty of tickets, oh that's right I just got one!