Maybe early days for there to be much shareable experience of these machines.
My immediate problem with the Vax "Dual Power" carpet washer is that two litres of clean water, produces an egg cup full of dirty water. If this is to be expected, I wonder why the dirty water tank is as large as the clean water tank. The dirt that is picked up is not flushed into the dirty water tank but build up thickly around the cowl covering the brushes.
Ive read the troubleshooting guide and followed the advice there, without any improvement.
Unfortunately my worldly good ar in a heap in the garage until the carpets get cleaned. This doe add to what would usually be a smaller problem.