I would recommend anyone doing their own work should get a "Torque stick" for the cars you will be working on. I use them in my shop all the time. At first I didn't believe they could actually work but after checking with a real torque wrench, I found they are very accurate. It doesn't matter which airwrench you use as long as it can supply the torque needed. I use cheap ($29.00) wrenches for day to day work and have a good Matco 600 ft/lb for when it is needed. I generally only use it to remove wheels put on by one of those tire jockeys at the tire shops. The torque adjustment on most air wrenches is only as accurate as the air pressure it receives, so I don't trust them. With a torque stick you just tighten until the lug stops turning. You can stand there for the rest of the day beating on it and the only change will be the head ache you develop from the noise.
Just remember, the torque wrenches only work when useing it with air wrenchs. Never use one with a breaker bar, you could twist it and make it unaccurate.
84 500 SEL (307,xxx miles)