I recently bought a 2015 Express Blackout standard cab that I wanted to build out just as a fun street truck without going over the top and building a track truck.
Based on recommendations from Sean, I got hooked up with a Diablo Trinity with 93octane/bolt on mods tune along with the tune for the 8 speed and ECU swap.
The tune with the mods that I currently have on it really woke the truck up. THrottle response is excellent, power band is much wider and has more go throughout it. It's exactly what I wanted in terms of performance.
The express standard does not come stock equipped with a rear sway bar. Had I left it stock, I might have gone a good long while and not known that.
Now when I punch the gas from a rolling start I'm getting enough torque at the rear that I get body roll. Hellwig RSB and moog links are next.
The tuner and tunes are so far the best bang for the buck that I've spent on getting this truck. If you are on the fence, the performance increase and just outright FUN you get out the truck are worth the money.