Hi Adam,
I did a lot of training with Ron Tiley, Prochem UK founder many years ago when they were based in Kingston upon Thames, when their was very little formal carpet and upholstery training available.
The training back them was excellent and I have no reason to believe it has deteriorated since Ron retired from training. If you are that close to Prochem's HQ I would recommend going on their training courses as you will gain a great deal of practical experience, and get a chance to try their portable machines.
I still have my original Prochem steam pro from the 1980s, with built in emersion water heater, still in working order. However, I've now got an Ashby's triple vac Enforcer, with again an in-tank emersion heater and a separate V2 water heater.
The new Ashby's Enforcer is in my opinion a far more advanced portable carpet cleaner than the Prochem models produced now. I still use a lot of Prochem chemicals, as I find them still to be very good products.
Alltec's machines are also well worth considering and I am looking forward to attending their IICRC carpet cleaning training course this February and seeing their range of machines whilst there.
Regards Phil