someone correct me if I'm wrong, but I believe the 94 stang was Motor Trend's car of the year as well. as for problems, well, just take out the stock mid-pipe and be amazed.
the best year mustang in my opinion.
1. better looking than a fox (curves and interior)
2. handles better than a fox (wider wheel base)
3. easy to mod and repair than a 99+ (pushrod motor)
4. most fox parts will work, or at least they have aftermarket parts (H/C/I)
5. problems are as said before, nothing major like a plastic intake that cracks (non-PI heads intake)
I have a 94' GT, and the only thing that has gone wrong was the throwout bearing and the stator in the distributor. The first thing I did to mine was just gut the cats and weld it back together. That alone made a huge difference.
As you can guess I opted to get headers, an x-pipe (no cats), and a turn down kit soon after. I noticably picked up a lot more top-end. Definately where it was needed. In my opinion, they're not much slower than fox cars. Plus they look way better. Plus if you really think its that much slower, come time to rebuild, just buy a carburated crate motor and have at it. The one thing Ford messed up on is the trans and the gearing. We needed a 6 speed and more gear a long time ago. Other than that I love my car.
I mean the mid pipe on our cars is extremely restrictive. It comes stock with 4 cats on it. Eliminating the cats or even switching in a pair of high flow cats does wonders for us.