I have a single jet 4" Glidemaster that I bought from prochem when Ron Tilly was a boy :
Water delivery, as Steve says, as far, far too much for upholstery.
If you are not going to be cleaning a lot of upholstery, then you will not be able to justify the cost of high quality tools such as the DriMaster or CFR, so your best bet would be a stainless steel specialist upholstery tool such as a "p1ssing in the wind" or guarded spray jet available from most manufacturers. Do NOT buy plastic or general purpose hand tools.
Safe and happy cleaning
The Ken