It all comes to personal taste. I love my 95GT and would not trade it for anything. I love that it was the "last year for the 5.0L". It is a nice looking car, but has an easily moddified engine. For me that is enough to never want to trade mine.
I'd go with the 94-95's. The Fox's are faster, but I think the SN95's handle better.
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White 1995 Mustang GT
Dynomax Cat-Back, Offroad H-pipe, a chip, K&N Filters w/o Air Silencer
My 1995 Mustang GT