Hey Kevin, not to be a bubble burster, but quiz the guys on how they get that much power out of an ECU change. Ask them if they eliminate "torque management". Ask them if their warranty covers your transmission.
Not saying their ECU won't make a change, it definitely will. But for that money there's lots of tuners that can make those changes and do it on a dyno.
See if there's anybody near you:
http://www.ls1tech.com/forums/sponsors.php

These guys seem to know what they're doing and I did ask about the warranty. He indicated it won't void the warranty and that there will be no adverse affects on the drive train. I am picking up the new H2 tomorrow and will ask my salesman to ask an H2 tech the same question. If the dealership recommends against it I'll just return it. I do want to install it though to see if there's a noticeable difference before making a final decision. Thanks for your concerns.

You're welcome. Be careful what you say to people at the dealership. The salesman probably won't know, but a good tech will understand "torque management" in the ECU. If the service dept gets wind of an ECU mod (especially a complete swap), you'll fight tooth and nails to get a tire fixed under warranty, let alone a drivetrain issue.
FWIW, not trying to keep you away from the product or upgrades, just want to share some info. Torque Mgmt is GM's method of helping trannys survive. Under high load/torque (full throttle takeoffs) the ECU retards timing. In the GM ECU tuning world, reducing TQMGMT is the first thing done to make a huge difference in drivability.

I appreciate your concern. I was involved in a scenario where I installed a Banks Kit on my 2001 3/4T Dodge Diesel several years ago. Right on Banks main website they stated that their product does not void the factory warranty. After installing the kit, I had a fuel pump go out after while the truck was still under warranty. (Keep in mind that Dodge had some issues with their pumps back then and even in 2004) When the dealership found out I had a Banks kit installed and I tapped into the injector wire, they voided my warranty. They could have overlooked this and replaced it without incident. I called banks and their solution was to take them to court.

Ooof...
Well let us know how it runs with the new ECU!

Be happy to. Sometimes I can be a glutten for punishment so if I keep the ECU and drop an axle, shame on me! By the way, I purchased another Banks Kit for my '04 1 Ton and I love it!! I did do a torque converter upgrade on that one though!

I'd hope the trans drops before the axle Really, I think you'd have to go out of your way to kill it even with TQM taken out 100%. I just wouldn't go advertising at the dealership is all
I've been screwing around with GM ECUs for 10yrs now, there's always potential for improvements over factory settings. I've got a spare one now that I need to have done for my 8.1L header install...

Axle, tranny, muffler bearing...they're all the same to me! I was told the factory pretty much has these tuned down quite a bit, but I know almost nothing about ECU's, other than it's a computer that tells things what to do and when. I'll keep you posted. May want to see if you can scrounge up a beefed up tranny for me just in case

I have the new Sierra Denali with the 6.2L and the 6 speed, and love it. It gets great mileage too considering.

I know the H2 is heavier, but it still has PLENTY of power.

variable cam timing, displacement on demand, 6spd auto...it's a quantum leap for GM and it's great stuff. Treat it well with good oil & filters; I'm curious to see how the oil-regulated cam timing system holds up.