I just leave Traction Control alone...
http://www.fiestastforum.com/forum/threads/14598-Traction-Control-caught-napping?p=247437&styleid=10
...it seems to take a LOT to get it to kick in. (and that's not a complaint)
Re Stability Control (a.k.a. Sport Mode):
I suspect that it's chief goal is just to keep the rear end in check.
Approximately 18 years ago I had an apartment in a different city. I opted to travel home during a snow emergency when everyone was told to stay off the roads. (because, bored) So being the only one on an untreated highway I could push the limits a bit. Well, I eventually found it... and managed to do a straight-line 360. I've driven under the same conditions before and after that time. That was *the* *only* time I've *ever* lost the back end. I knew and understood exactly what I did to initiate the 360. Putting too much torque to the wheels in attempt to accelerate too fast, I lost traction on one wheel, tried to accelerate harder for the speed loss, vehicle starts to pull to the side that has traction, while holding throttle I attempted to (over) compensate and (too) quickly turn into the side that doesn't have traction, then (too) quickly tried to straighten out and... it flings back in the other direction initiating a 360 as I attenuate throttle control.
Even playing around with the hand brake I've never come close to loosing the back end. Bottom line, I leave SC alone too. I already know how to drive. The car isn't RWD, doesn't have an ass to speak of, is lighter weight and doesn't have enough power in stock form to really justify TC and SC on dry pavement.