I currently have a Simpson Cold Water Machine 3000PSI, along with the Simpson Surface Cleaner(Hoover Style). They are both 4 years old. This is the only experience I have had with a Surface Cleaner so I really dont have anything to compare it to. The model I tried and even the one I bought always cleans much better on the edges, and requires quite a bit of touch up work. My question, do surface cleaners function well with cold water? Also I am considering buying a 3500PSI Cold Water from Delco, will the additionl pressure make a big difference with the surface cleaner.