we almost bought a new aspect, price drove us off. Anyhow look at the current trailer life, they have a test on the itaska made by winnie and I was surprised, at what I saw. The system on a e450 chassis is alm oste maxed out with just the unit itself. I think there was less than 2000 lbs load ability which includes fuel, people, property water, etc. Plus it showed less than 10 mpg for the test and was not raved about power wise overall. Seems it was found to be just adequate and I think the aspect is heavier?