Looking at renntech's power output, it looks like it's slightly less than factory European power levels for some of the OM642 implementations. Some chassis integrations have 260 hp and 450 lb ft of torque, which is a tad more than 258 hp and 400 lb ft that Renntech shows. Most chips I've seen push boost to the limits of fuel injection, but in this case, it seems like Renntech's tune is in the realm of power outputs from the factory. Gives me a little more confidence that I would not be going too out of the norm for what this motor was intended for.
I can maintain traffic speeds at 8K lbs up and down I70, but around 10k ft my foot will be to the floor, which is probably around 85% actual load compared to sea level. Assuming about 15% power loss at 10k ft, a Renntech's tune at full-load is about factory US power levels for the OM642 (in other vehicles). Since I can maintain traffic speeds without a tune, I'm more in the power load profile of a passenger car than a loaded Class C towing a second car (which would likely use full 400 lb/ft of torque for long durations of time).
There's no free ride as it pertains to longevity of a motor and power output, but this feels reasonable vs a car that gets a chip and it's pushing 50 hp over factory power levels.