I don't know how many tuners you have tried in the area to come to the conclusion that they all suck.
I agree that Sutton Ford is a very good shop to take your car to. Jerry & Doug really knows their mustangs.
Speedinc in the Roselle sandwich has a good reputation. They mainly do LS1's but dyno tune mustangs & Cobras as well.
Street stuff in Addison is supposed to be good but I have no experience with them myself.
Joe