Here's my two penn'orth on my Prochem Blazer Plus, bought two years ago. Their service is good, any bits you need are there first class post next day. Drawbacks: water pump only rated to 1000psi so not up to powerwashing as an add-on. Engine 18hp B&S Vanguard quite noisy on small housing estates. Water tank badly designed - no internal baffles, fill through the large filler cap
(modded mine with bog standard ballcock valve); heat exchanger can leak water into exhaust; it also bypasses water straight to waste tank so if doing a flood extraction you need to start with a tank of water! ( another mod - pipe it back to the water tank through a bit of hose as I did. Seems to work.). Otherwise its good kit and later developments may have cured these probs. I gather Chemspec offer a good t/m with a 3000psi pump but I have not seen it in action.