Hope i'm not too late with this,
I recently got a hypertherm powermax 45...it cuts up to 1" pretty easily and is supposed to cut a fair bit thicker than that.
I was worried my workshop power supply wouldn't handle it as it's only 30 amps at 240v. This seems to be enough though, to run a 3 hp compressor and have the plasma running at full amps.
I have just about finished setting up a new air system with better filtration to supply the plasma.