I have an old ariens 24" 5hp that I was tired of working on. I was all set to buy an Ariens 11hp, went to the Home Depot the day after a storm, and they were sold out. My daughter and I looked around the store and finally, out in the garden department we saw 12 of the 11hp models. Evry single one of them (two still in the original boxes) were marked defective for return.
After seeing this I decided, thanks to a great post on this site, to buy a new engine for my old war horse. I ordered the 7.5hp Intek from smallenginewarehouse.com for $222 (free shipping). They sent me an 8hp for some reason but after drilling 4 new holes in the deck to mount the engine, putting some gas in and pulling the cord it started right up. Now all I need to do is move the chute control linkage and I have a really great snow blower :)
From what I've read, if your worried about quality, the Hondas seem to be very well built and well liked, although they are pricey.