Hey, welcome to the scrum.
So sorry the first rental you looked at smelled bad. They aren't supposed to, of course, so I wonder what was going on with that one. I'd highly recommend renting one (that doesn't smell bad) before even considering buying one. In fact, I'd urge you to rent several times before buying. Doing so it much cheaper than finding out you don't like it after you've purchased something, and it will surely educate you about features you might or might not find useful.
As for the Keystone brand, they do have a fairly good reputation.