I haven´t driven the current V6 but I think its actually very good. Most people tend to only look at the engine difference but the suspension differences are also very relevant. I had a 2010 V6 with the old 4.0 engine (nothing to do with the current 3.7), but I can tell you that besides the engine, that car had a terrible suspension. It was very bouncy and had a rough ride, the car handled bad (no lsd) the power was merely decent for city driving. My old V8 03 GT was ages better. and when I traded the v6 for a same year GT it was even more amazing the difference in the way the cars feel (same year cars V6 vs V8, obviously the V8 is faster but the suspension is also ages better)
I would test drive both cars. The GT has an obvious performance advantage (which not all people need or want), but definitely feel both cars before making your mind. I honesty prefer the GTs
The non trackpack GT has **** for suspension - especially if its on the 18x8s with the 235 Pirelli's. That combo is outright dangerous for a 400 hp car. It handles like absolute crap and is the first thing you should address if you end up with that combo. The track pack isnt much better but at least it has 19x9's, 255's and Brembo's.
2011 Mustang GT M6 3.31s
Matt HONEYCUTT Tune, Lethal Off-Road X, GT500 axlebacks, J&M LCAs, UPR UCA, Whiteline LCA relocation brackets, Eibach Pro-Kit Springs, Koni STR.T shocks/struts, GT500 strut mounts, SR Strut Tower Brace
Best 1/4 E/T (05/18/14 MIR - no tune, X-pipe, or UCA): 12.920 @ 109.40 mph (2.059 60ft)