Yeperz... that's what Generations carries. Not sure why he calls it the P-10, but he does. Maybe he'll chime in. I just like the P-10, because it's all one unit. It's super quiet and it pushes the Piranha to the max. 2 of the 505's would be pretty close to the same output, so it's more a space and convenience thing. Plus one M-10 is cheaper than 2 505's.
The LPM is how many liters per minute the machine produces. Basically it's volume. PSI is pounds per square inch of pressure the machine opoersates at. This is how hard it pushes.