You need to talk to some of the chip companies. Some years back I chipped a Suburban 2500HD and finding a chip for that engine was enlightening. Most of the chip companies hung up on me when they realized what engine it was, other got real evasive on the benefits of their product.

First: most chips require premium gas.

Two: They provide their extra performance by a different injector map and advancing the timing as much as possible, determined by the knock sensor.

Three: this advanced timing can result in elevated engine temperatures while towing, especially on hills. Changing theromostats may be advisable, as is adding an oil cooler if you don't have one (the Suburban did).

I ended up buying a chip from The Turbo Shop out in California and was quite happy with the results. The owner spent almost a hour on the phone with me at no charge. His chip wasn't the cheapest, but it was worth the extra money. He solved the QC issue some vendors have by reprogramming factory chips and his didn't require premium gas.

I swear by B&M shift kits. Worth the money. Never tried the electronic versions.