I have a Hawk PU II and although its nice and will run other machines (with limitations) I really don't think its worth buying one unless you only intend to tattoo with Hawks. Even then, you lose out on being able to fine tune your machine as you can only pick the Hz in increments of 10 (which is pretty useless for most other machines). As far as Hawk performance goes, I've not seen it make any difference so, unless you feel like yours is running erratically I'd save your cash or invest in some spare grips.