I got a chance to take a look at one of these in person. The thing would run off of a 2kw briefcase generator if you drained the stack before starting it. The HP stage output temp maxed out at 130f after 10 minutes of running. It has 2 cylinders that look to be the same diameter. I do not know if the second is coaxial or not. LP steel tanks that had been filled to 1800 psi previously registered 2ppm on CO. The one 3,000psi tank that we filled registered "high" which is what my palm meter reads when the number gets above 25. It is possible that we may have sucked in exhaust from the generator. The PM valve is said to only hold at 500 psi. This one held at about 2kpsi, as would be normal, but the valve leaked down after the compressor was shut off. An ambient temp of 86f is said to be the max that you can run for extended periods of time without changing the cooling water in the tank. The whole thing is small enough for me to pick up by myself & move around. the ergonomics of the handle placement is good.A little more info on the Mantus compressor -
Second stage rings should be changed after 200 hours
The filter cartridge looks like a Bauer P0 filter. It is said to last 20 hours
I hope to have more info in a few days.