I'm getting ready to start a solo lawn service, and thanks to some very good advice here, I've decided to purchase a 36" WB mower. I've noticed that some manufacturers list the ground speed of their WBs, and some are about 7 mph. I've never measured my own walking speed, but it seems like I've read that an average walking speed is about 3.5 mph. My question is this -- Assuming that I'm in fairly good physical condition, is it also reasonable to assume that I can crank out a full day's worth of 7 mph WB mowing? Also, I think that Toro WBs have an optional standing platform. Do these things work?