What is your criteria? What characteristics do you WANT?
I see Shelbys as more focused on the fact of BEING a Shelby. Yes, a lot of ways they are great, but it is more for the label.
Roush (while still being conservative) seems to want to make Mustangs how they believe a Mustang should be- same with RTR, and Saleen, and so on.
I am not saying one is better than the other, but looking at them, which do you feel is closer to you? I LOVE GT500s, but many of them seem more attention grabbing than anything else. By all means, the other companies do this, but it is very easy to get a subtle Roush, or other model.
Luke 11:9-10 “So I say to you ...*search and you will find; knock and the door will be opened to you.