dleonard,
First, you do not indicate the type or rig, brand, model, gas, or diesel. Details are important when posing questions.
Second, DO NOT DO IT! An added performance chip cost me, and others an engine. I recently had two pistons, #5 & #7, burn out due to a high-performance chip being installed and run for 10K miles.
The Service Manager at the repair facility said he has seen this type of failure before and my online research indicates the same. A number of RVr's have posted to these forums that they, too, experienced the same, exact type of engine failure as I did. All from so-called, high performance enhancing program chips.
$12K later, I have a factory rebuilt, 18 month warrantied GM 8.1 ltr engine. The only engine performance enhancements I would do (previous owner had chip installed and it was NOT disclosed) would be a Banks exhaust system, and/or heavy duty plug wires and additional cooling features.
Just my 2c.
Happy Trails!
Darryl