Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I'm sure this has been answered many times already but I'll ask again.  I have a toro 826 dual stage snowblower and would like to add a single stage toro.  One of our local dealers is having a sale on these units.  He has a bunch of toro 221Q and 221QE models from 2009 and 2010.  He also has several 621 versions from last year left over.  Price wise, the 621 are about $25 more.   The 621 does seem to be quite a bit larger than the 221 in frame size.  The questions I have would be:
1. 2 stroke or 4 stroke?
2. Electric start or not?

Thanks in advance for any responses.