I have a 110VAC, ~250 lb-ft (IIRC) Craftsman electric impact wrench, and a DeWalt 18V 120something variable speed cordless. I very rarely use the big Craftsman, because the little DeWalt is not only more compact and convenient but much easier to control. I can comfortably use it on fasteners that will be torqued anywhere from ~35 to ~120. That isn't because of the variable speed, which isn't designed for continuous use (mostly useful for slowing down while removing parts that are already loose to avoid slinging them). The power level is just a good match for the job for most automotive wrenching tasks, so I can easily control the torque by just releasing the trigger at the right time. I usually use a torque wrench for the final tightening anyway.
I have used the DeWalt (as an experiment) to loosen a rusty lugnut on my Dodge, which was torqued to 135 before being exposed to a year of salt and rain with no hubcaps. I doubt if it would make it through a full set of 32 studs on one battery, but changing one tire is possible. Admittedly, that is at the extreme end of it's range, and it isn't really the best tool for that job. With the 100 lb lugnuts on the Camaro, battery life is a non-issue.
The key limitation is that extensions sap a HUGE percentage of the power. The socket needs to be directly attached to the end of the DeWalt. The added mass and slop of the extension leaves the impact gun thrashing away while accomplishing nothing.
BTW, I'd be wary of lithium batteries in an impact wrench. They are dangerous enough and all too common in electronic applications, but subjecting them to the shock and vibration and other abuse of an impact gun, especially one that will be bounced around in a hot trailer, seems like asking for trouble. Unlike other battery technologies that may simply rupture if they fail, lithium-ions are explosive and highly flammable. FWIW, I've even had a near miss in a laptop, which lives a far gentler life. "Luckily", it was on my lap at the time and I was wearing shorts, so I noticed the sudden and pronounced overheating very quickly, and promptly took the battery outside

While it did not explode, it did get very hot and swelled up. Had I not been there, it probably would have started a fire in the house.