I see you just moved to Texas...Welcome....
Anyway, I think those guys are reputable. They have major advertising layouts in most mustang magazines. I bought my emblem kits from them, fast shipping. But it all depends on what you are looking for. If you live close to San Antonio, you can get a custom tune from the famous NMRA racer, Mike Murillo at Murillo Motorsports. He did several tunes for me when I had my supercharged vert. He is rather expensive on parts and installation, but it all depends on what you need. Check out the following sites:
http://www.uprproducts.com/ http://www.steeda.com/ http://www.blueovalindustries.com/
(the last place is probably the cheapest around for 5 lug/4 wheel disc conversions)
http://www.cjponyparts.com/ http://www.jdsperformance.com/index....tem&inmake=all
(This place was the cheapest around for my 15# supercharger pulley and walboro fuel pump. The guy can get other stuff not sold on the website. He also gave me an additional discount over the phone.)
Good luck...
__________________
1988 Supercharged 'Vert - SOLD!!!
1970 F100 - 10 bolt posi Rear end, Fuel Injected 302, Traction Bars, EQ shorties, Bed Cover, Custom Interior with power leather seats- custom dash/console, AOD w/ B&M shifter, Tubbed w/ 15x10s rear and 15x7s up front, no emissions junk and it's LEGAL!!!
"Only two defining forces have ever offerred to die for you: Je$us Christ and the American G.I." - Author Unknown
Calling all North Texan's 
I've bought a bunch of parts from them and I've got no complaints.It was all stuff for 65/66 cars, though.I couldn't really say anything about their late model stuff.Hope that helps.
