I received my SF3 tuner from Southern Speed yesterday with an 87 octane performance T4 tune and a 93 octane performance T4 tune.
I ran a stock 0-60 with my g-tech and loaded the 93 octane performance tune to run another 0-60 but the traffic got too thick in the industrial park so I had to go back and run the 0-60 this afternoon. Besides it got dark on me last night making it too hard to tell if a car is a cop. It takes a while on the first load having to upload the stock tune to the tuner and all.
The daily driving manners are very good at light pedal. The slop is taken out of the shifts making them quick but not abrupt so they still feel smooth enough. It also moves up through the gears quickly not holding out any gears. This should be good for gas mileage. If you start giving it say a quarter pedal the shifts firm up more where you start to feel them and you are at 60 in no time compared to stock. If you floor it the tires bark going into second gear and you can tell it feels faster.
Stock 0-60 was 6.51 seconds. The 93 tune 0-60 was 6.02 seconds. That's a half a second (.49) better or basically 5 tenths. The 93 tune 0-60 was on a very slight incline on top of that. It was the only clear place I could find to run and I wasn't going to go downhill any so I would have to hear about that from the peanut gallery. Traction control was on for both comparisons.
I would definitely say a tune on a 5.0 was worth it for me. I corrected my speedo for the 20" wheels and took a half a second off of my 0-60.
I'm not saying this is the best tune out there because I have no other 5.0 tunes to compare it to but if it's not then it is real close.
Here is video for a certain someone who is so untrusting.