I've had my SRT6 since May... LOVE IT! Only just recently broke 5,500 miles on it.
There are some here who have had warranty issues and some bad luck with the car in general. (lemon lawed, blowing tires, etc).
I had the opportunity to test drive a Mustang SVT a few years ago, before the new body style came out (they finally got it right), but it wasn't 'all that'.
I'd have to say my SRT6 kicks me in the pants much better than the SVT did.
Note: I also have the cargo cover installed. I was surprised it was not 'standard' equipment.