I picked one of these up just to see if it would perform as claimed. After 6 months of use here are my findings:
Pros: This impact produces an incredible amount of torque. It has very little recoil so it doesn't try to rip your arm off a the limits of what it can do.
(iATN Note: At the time of review, this product was titled "Earthquake XT Impact Wrench by Harbor Freight").