I have used it but not as my primary method. Slower than HWE for most situations, but not a lot slower. For some stains or some sensitive materials it can be faster than HWE.
The only person I know who uses vapor steam cleaning on a regular basis is Steve Andrews. I have not seen him post here recently. You might find him on one of the other boards or send him an email sandrews841@gmail.com
If you are using as primary you can say it is little bit slow.It is faster in some particular area on furniture where normal machine not work perfectly.