I have an 03 700 with stock dpm that has had many of miles put on it in MN as well as many more in the snowies at 10,000 feet. It has always run like a top at either elevation. 7000 miles on the motor with a quick set of cheap pistons as a refresh about 1000 miles ago. Change the weights and go. I do mix just a little bit of oil in the gas when in the mountains as cheap insurance though.