Things I liked: I like the dual air tanks and the resulting number of shots that I get. It looks great and is very accurate.
Things I would have changed: Initially I had no problems, but after letting it sit for a couple of months (with the tanks pressurized) a leak developed. I sent it back and it was replaced with a new Monster. The same thing happened again to the new gun. Anything above 1000psi leaks out. Now it is back at Pyramyd again for repair. Two guns with the same problem means that there was either a bad batch of o-rings or a design flaw with the gun itself. Maybe I should shoot it down to 1000psi every time.
What others should know: Pyramyd's Customer Service has been pretty good so far.