J.H.
I wouldn't use any of them. You can't ever get the water as hot as a professional cleaner does so the carpet doesn't get that clean. Also it doens't suck up as much water so the floor stays wet longer and the more you walk on wet carpet the faster it will get dirty again. The wet carpet actually attracts dirt. My mother has bought a rug dr in the past and she ended up using a service. I would call around to a couple differnt services and see what they have to offer. A great small family owned one is Cosmopolitan Carpet Cleaning. They are my inlaws so I know they are great. Dalworth is also a really good company. I hope this helps I would hate to see someone spend money on something that won't be worth it.