After many hours driving, three hours round trip and sometimes having to come back the next day I decided to pull the trigger on a compressor. I know I paid too much for this muffler but I was tired of half measures that ended up failing me. So I got the thing in a crate, it was rattling around inside upon delivery and the low pressure air intake filter was broken off. They sent me another one so I got to use it.. It seems to be a good unit, still Chinese but better built than the ace eagle or whatever they are calling them now. So I filled an empty one hour S.C.B.A. to 4500psi and topped off my guppy from 2800 to 4500. It should be a little faster the next time as I was playing with things a bit while filling. It came in around four hours and forty minutes for the both. I guess now my main hope is I can shoot enough to make it worth the investment..