Hi Andy
I have only had a try of the 13hp a few weeks ago (Dave Powers)
Of course the latest 13hp have a bigger blower and smaller pump, but Daves early model seemed to pull very well any way.
Noise wise - this is nothing too great, perhaps a bit nosier then the Avenger that I had but that was a twin, this is a single so its a bit like motor bikes - you can count the bangs easier with a big single.
The 15hp has a bigger blower still and also a 2000 psi pump like yours, so I would imagine the performance of this is better then the 13hp - which is more then adequate on domestics and most commercials.
Clinton
The machine sits in a frame (13 hp the same) thats supplied, and you can fasten the frame to the floor.