Pete, I don't know what you want for proof, you get the cfm
OR the waterlift from two vac motors, you can not have both! That would require 4 vacs and two stand pipes in the tank.
pick your poison, you want air-series vacs, or air-parallel?
And it's got nothing to do with
Prochem, we have lots of good PC dealers, it's just an uneducated salesman that is misdirected.
Since I'm the "rain on parade" guy today, might as well drop a bomb.
On these smaller DC pumps, your operating pressure is directly affected by the jetting on the wand, a "500 psi" pump may only deliver 1/2 of that pressure with a decent wand, to get "full pressure" from it, you would need to have installed tiny jets on the wand, which is actually counter-productive because you are now misting the carpet with a finely atomised spray, instead of rinsing the carpet with some decent water flow.
Now, that said, if you can get 300 psi from it with a pair of 110 03 jets, I'd be happy with that as a balance point.
Heat: there are very few elec. heaters that will warm a tank of room temperature water to 200ºf, let alone higher. And you would cut that final temp by 50-70ºf if you used my wand jet example above. I don't even want to think of what you would have if you started with some real cold water like so many do, and what salesmen tend to indicate when they reference 209º!!!
I would slam an extra quick connect into your sol. line, and drop it into the tank, and let the heater run for 15-20 mins. in constant cycle with a full 12 gal tank while setting up the job, hopefully you get it up to 120ºf by then, and now when you clean, as your pre-heated water is reheated for one more cycle on a 33% duty cycle, you can get a nice boost on the fly. You will need to repeat this every 12 gal.
If a unit has a true 200cfm (air-parallel), try and make use of 2" vac hose with a 2" hook-up on the machine, not as important with a 100 cfm machine.
I hope this helps a little.
btw: I don't know if that Mytee is 240v. but it looks like a good buy locally.