On your original question...which brand of air drill...
I've been getting air tools off eBay and Craigslist lately, which has me considering other aspects of my tool buy, such as availability of rebuild kits, if I end up with a lemon and need parts.
I have found that generally, IR rebuild kits are more readily available and CHEAPER than Chicago Pneumatic kits/parts. Not something you'll need for a while, but may factor into your purchase decision, if you are thinking about a tool which might last your lifetime.
This seems to particularly matter in tools which wear out more quickly, like impact wrenches. I really like the design and quality of Chicago Pneumatic...I think they build the better tool. But, in the long run, I'm going to have to rebuild that impact wrench if I use it a lot...and the rebuild is only going to cost me about $25 with IR.
Drills seem to last better...I just got a Chicago Pneumatic CP 787 drill online for $10. I took it apart, cleaned it thouroughly, re-greased and lubed it, and it purrs like a kitten. It has clearly worn out more than one chuck (The chuck which came with it was not functional and not the original), but the internals are still in perfect working order.
If you are primarily using smaller drills (1/4 inch or smaller), then I'd go with a 1/4" drill...even the 3/8's drills are fairly heavy for frequent use.
Just my 2 cents...hope it helps with your decision.
