Anyone have experience with these? The swivel front wheel self propelled commercial 21" mowers start at $499. http://www.badboymowers.com/view/swivel-push-commercial-pricing And the fixed wheel 21" starts at just $399, not sure if this model is self-propelled though. http://www.badboymowers.com/view/fixed-push-commercial-pricing Looks like these are the cheapest 21" commercial grade designated mowers on the market. I'd love to hear more about them.