Duramax Programer

I have an 03 2500HD with the Duramax and I'm considering a programer. Can someone lead me to the best one for the Duramax?

Also any results from some of you guy's that have done it would be nice.

Thanks
Mike

I have an 03 2500HD with the Duramax and I'm considering a programer. Can someone lead me to the best one for the Duramax?

Also any results from some of you guy's that have done it would be nice.

Thanks
Mike

They do help and make a differance.
But if any warranty left on it a programer may interfere with the warranty.
MT