As a 7.3L guy, you have to love when your tuner offers free lifetime reburns...
It helps out a bunch, especially once you've modified your truck to the point where a tweak here or there is needed from time to time. In my ’97 F-350's case, it hit the dragstrip back in late June, and experienced some slight shifting issues. The 1-2 shift was perfect, but the 2-3 and Overdrive shifts were a bit lazy at WOT and I noticed they were occurring around 3,800 rpm. My best pass was a 9.07 at 78 mph in the eighth-mile that day, where as without the delayed shifts, I was sure I would've seen the 8.6 to 8.7s (at a hefty 7,600 pounds) I expected to see.
According to Matt Robinson at Gearhead Automotive Performance, the '94.5 to '97 Fords don't shift exactly where you command them. The computers don't have a hardware delay time parameter like the computers in the Super Duty 7.3L's do. To fix the problem, Matt programmed the chip to tell the truck to shift well before it's time to do so (on the higher horsepower tunes, anyway).
Once this new six-position chip is on, I'll be off for a test drive. But the only way to make sure it changed things is to hit the dragstrip again, which I plan to do in the next few weeks.
PS - Other trucks running in the 9.0 range that day in the eighth-mile were doing so at 74 mph. The fact that the '97 was trapping 78+ mph told us the horsepower is there to run 8.6/8.7's in the eighth and 13.5/13.6's in the quarter-mile at full weight.