what is the best handheld tuner for 99+ mustangs and what results have you seen after using them

I love my SCT flasher :) Of course, there wasn't that much to gain on a stock motor (about 7 hp and 3 ft lbs at peak, or something like that) However, you can tune out O2's, traction control, etc.

sct has become the standard

I had a mail-order SCT chip(93 octane) from MD Motosports and loved it! I would head over to www.modulardepot.com and see what they have to offer you.

Sct Imo.

SCT is what I use and I like it.