I'm really undecided. The two guns I'm considering the most right now are opposites (kind of) - I want the Ultra Lite for it's smaller size, but love the Mountaineer for the thumbhole stock.
The Mountaineer is also quite a bit cheaper - I could basically get a scoped Mountaineer for the price of an Ultra Lite, but I have to hunt muzzleloader season with open sights anyway so a scope would just be for fun/load development.