[rames14]

We have an ei2000 and an ei2000 Companion. One was purchased in Wisconsin when we lived there and the Companion in Colorado. Both have worked fine both at low and high altitude. The only issue is losing power as you gain altitude. But, we only use ours for coffee, TV, lights and charging. When we boondock, we generally don't use A/C or the microwave. We live at 7500 feet and travel between sea level and 10,000 feet.