IR ThunderGun Impact Wrenches any opinions?

I've had my Snap On for 16 years with no complaints. It still hits hard. As stated lubrication is a must. It busted loose a ball joint in My 78 Dodge truck that I couldn't get with a long 1/2" breaker bar and cheater. IR and Chicago Pneumatics are are both industry standards that I wouldn't be afraid to buy.