I have used a few different kinds of air hammers over my last three years or so of wrenching, and am a combine tech so I know what you're looking for. In my opinion the Snap-On PH3050A is hands down the best hammer on the market. I have used a IR, a John Deere (whoever makes them) and a Mac and none of them even compare. The Snap-on model does not have a variable trigger, but it does have an easy to use air adjustment knob that makes it easy to turn it down if needed. As with most things that say Snap-on on them, you have to pay a high price to get it but in this case it is deffinently worth it!