do programmers really help

I added a Bully Dog GT tuner to our GMC 2500 with the 6.0L vortec motor to correct for larger tires and new ring and pinion ratio. For the first year I used the "normal tune". The second year I switched to the "performance tune" and the difference is amazing. Hills that previously slowed the truck (while towing)to 45-50mph in 2nd gear now maintain 3rd gear with the torque converter locked. I can even gain speed on those hills if I need to. No change in mpg for me, but It does require premium fuel in the performance tune. It can also adjust the shift points/firmness if you want it to. And it has a gauge display that can display up to 4 gauges at once. I use rhe trans temp gauge because is shows when the torque converter is locked. Also has a warning beep that you can set for high temps (coolant or trans,etc). A custom tune from some of the others can produce better performance, but lacks the gauge display. Bully dogs web site claims they can do these custom tunes in 2015, but provides no links to any further info.