Particularly when working around upholstery I like to use something that will not snag and cause possible damage to the item being worked on.
For this reason I would recomend getting some length of hose where the solution hose runs inside the suction hose (hide-a-hose).
May not be ideal in terms of air flow, or if the solution hose bursts, but IMO the fact there is less to snag is more beneficial.
I have not used it on a Ninja but I would not anticipate any problem.
Pressure will need to be turned down to about 150psi (or thereabouts)