Conquest Super Nova 6331 - Real world towing question

[Dane]

Hi, I'm new here and will soon be new to the world of motorhomes. I'm planning to move up from travel trailers next year and am basically looking for the shortest motorhome I can find that can tow 15K. This has lead me to look into the Super Nova 6331, specifically late 2000's. I can't quite swing a new one of these suckers yet. My question is, how do they tow? I realize they are RATED for 15K towing, which is great, but I live in Colorado and I'm hoping that I won't be doing 15mph up the mountains here when I slap a truck or jeep on a trailer behind it. Heat could also be a concern. My setup will likely be a flatbed trailer with an F150 Raptor on it or a Jeep and a couple of sportbikes. Either way, counting a couple other widgets the max I'd probably be towing would be around 11-12K. Can anyone give me some good insight on what kind of performance to expect? Obviously I won't be breaking any land speed records, but I don't want to be suffering at a snails pace either.

Thanks!