I had this same decision to make last year, it was the 221QE versus the 421QE (now 621QZE). Both were so close to being the same performance wise, but different enough to make deciding difficult.
In the end, I chose the 4 stroke version, because I prefer the quieter (lower tone) sound and the extra grunt it seems to have when handling slush. I went on a limb and chose the new unproven engine. The carburetor did develop a fuel leak, it was taken care of under recall and warranty. In fact, the snowblower was just delivered to me this afternoon. Besides that little hiccup, I'm happy with the decision. That engine feels just as powerful and torquey, and sounds the same as a Honda GX160 that's on the HS621 snowblower. Time will tell if it will hold up as well.
Whichever model you choose is the right decision comes down to personal preference. But definitely get the quick shoot. This is the icing on the cake that makes Toro so desirable. No one has ever regretted spending extra for that feature. The electric start isn't necessary unless someone else might be using on occasion and have difficulty pull starting.
This message was modified Nov 27, 2011 by aa335