I cannot imagine having access to shop air and still using cordless electric for anything beyond a 3/8" drive.
On the 3/8" drive impacts, I've used Snap-On, Makita, DeWalt, and Milwaukee.
The Snap-On has easily outlasted them all, and I still use it today, daily, a LOT. It's a CT8810A, it's the second one I bought, the first with Lithium Ion batteries.... I'm currently on my fourth pair of batteries. It's strong, but most importantly it is TOUGH. It's been dropped, run over, got just about any fluid you can think of splashed on it, and it still works perfectly. I don't remember when I got it , but it was before 2015 because that's when we moved to the new building and I remember moving the charger then. So probably 12+ years of daily use.
Makita was a dainty POS. I broke two of them, then decided the rigors of automotive work is just too tough for them. I limited it to very light duty clean work (like dash work) but I broke it anyway. I still have the drill that came in the kit and still occasionally use that but the batteries don't have much mojo anymore.
DeWalt was fine, except it required the larger Ah batteries, and those literally shook to pieces. When I went to the DeWalt store to ask for replacements under warranty (both were broken within 6 months), the dumb broad at the counter asked me if they were subjected to any "impacts". I told her the word "impact" was literally in the name of the tool, so, yes, yes they were subjected to very many repeated impacts. They gave me two new ones. Those were both broken within a year. Come to find out, it is a pretty common problem, and you can buy aftermarket replacement battery cases for them (DeWalt doesn't sell just the cases). So I did that, recased them, and took them home to use in all my other DeWalt stuff that uses that same battery form factor... stuff like the leave blower, weed wacker, radio, flashlight, drill, planer, saw, etc. all work fine. Shame because I still have the tool, but can't reliably use it. Recently got a cordless grease gun that also use those batteries... a necessity for servicing the new Bobcat as it takes nearly a whole tube worth of grease every 10-15 hours.
Milwaukee is pretty decent. Not as tough as the Snap-On, but pretty close. And like DeWalt, they have a plethora of tools that use the batteries. The Fuel line is the better commercial grade stuff.
But for 1/2" drive or greater... man, my 20+ year old IH Composite impact gun will handily take care of all that stuff. And on the couple items it cannot (Honda crank bolts, some VAG product axle bolts), I pull out it's big brother, a 3/4" inch monster (it's the biggest one that doesn't require the second handle), and in one or two 'dugga-duggas' anything is cracked loose. It doesn't even notice, LOL.
The thing with cordless is, the batteries are an ongoing cost. If you use them a lot, they wear out. If you don't use them enough, they die. And those really end up being the most expensive thing with most of the tools. The tool itself may only be $100, but the battery might be $200! That's why if you have a bunch of tools that use the same battery, you will get more use out of them. They need to be used somewhat regularly. This is why I'm scratching my head at the cordless electric lawn mowers... my brother tried that, and every season the battery pack is unable to hold a charge like it did the season prior, so he has to go buy a new battery... which is nuts expensive. You could literally buy a new cheapo gas lawnmower every year, a whole season's worth of gas to cut his little yard, and it would cost less money.
It will likely come to pass I build my own pack out of premium cells at some point... 
