I've been loving the pen style machines as of late. I have the Bronc rotary pen from Hummingbird which is a very nice machine. Hits harder than the EZ pen so I've been using it as a liner. I just got the new Rambo pen from EZ today and got to do a small piece with it. They def did something different with it versus the Filter pen b/c it is literally dead silent while running and seems to run at lower volts. I equate quite with smooth and you literally can't tell the machine is turned on. Also, if anyone is wondering how the new NATS carts are with the membrane in them, they are pretty awesome. No weird tension or anything like that and they run smooth.