B

I agree, but the inside water sources for these are drying up. A lot of today's kitchen and bathroom faucets will not connect to our equipment.I solved more than a few residue problems for commercial customers with that machine. With a scrubber or "crb" its a good total cleaning system as well.
As long as there is a water source and discharge area, it will beat using a conventional portable, especially if the previous cleaner left a ton of residue in the carpet.