Can't tell where you live, but the IGO, when we looked at them back in 2012, did not have any kind of ducted heat from the furnace which was a big "no deal" for us. The furnace literally looked like the one in our old pop-up camper. The dealer, Hilltop Trailer Sales in Mpls, couldn't explain why Evergreen did that with for the furnace and they seemed just as disappointed with the design. In fact, the following year or so they stopped selling them.
The other draw back for us was the narrower design. For some who don't want the space it might be appealing but not for us.