is the Scag a gear-drive? if so, weather or not you get a stander or another walk behind, definitley go hydro! we also do mostly residentials, and recently purchased a 52" stander which are all hydro, and it is awsome. if you can fit a 36" in all of your back yards i would stay with that size, and get a stander. of course i dont know what you have to spend, but the standers are worth every penny (and they do cost a few pennies)!