Yea I haven't bit the bullet yet and buy one, when I do I'm going after any old DSP switch where I have to drill a hole in something. The other thing I'm having a hard time with is messing with my ECM, I would rather not mess a very important item like that up. I would much prefer to let somebody that has done it a few times install it. If I work up the courage to do it I will test it out and let you know.
I plan to go with an EFI tune at some point, fortunately I know the owner of a shop that has one of the best Duramax tuners in the country. I did the HP tuners thing as more of a temporary, a buddy of mine owns the tuner, I bought the credits from him mainly so I could kill my speed limiter and a few other things.
http://www.btdieselworks.com/product...t-dsp-5-switch