KF, I have a Craftsman compressor I bought about 4 years ago (went on a tool-up binge) that has done more than anything I've ever asked of it (pnumatic tools including impact wrench, air hammer, grinder, paint gun, cutter, sander).
http://www.sears.com/shc/s/p_10153_12605_0...Air+CompressorsIt hasn't given my any troubles, but one modification was needed to be made. The drain plug was utterly useless and horrible. So I did this:
http://www.hammerzone.com/archives/worksho.../ball_valve.htmI'm finding that Craftsman mechanical equipment is becoming junk! I'd love to stay with Craftsman, but after the experience I've had with my $400 lawmower that I bought 18 months ago, the broken drawers of my tool chest, and the broken bearings on my shopvac/leaf blower motor (3rd time), my loyalty to stick with Sears (beyond hand tools), has evaporated. But, the air compressor has held up just fine.
It is LOUD though.
What you want to look for: PSI capability isn't all that important above 90 psi, as you'll find most of the hoses and tools are set to max at that psi. I don't think I've got a tool that goes above 90psi. Tank size does matter though, but there is a balance to be had. The larger the tank, the more "drive" you'll have behind your tools. But, you can counter that by the strenght of the motor "gets more expensive though". If you have a smaller tank, you'll want a stronger motor to replenish the air strength. So in this regards, look for a quieter running motor with some hp. Just about anything will run a paint gun and palm sander/grinder. But, trust me on this, those are the things you want to do now, but tomorrow might be a different day and you'll want to do more. My advice is to over-shoot what you want today, so you're capable of doing more tomorrow. The compressor is the most expensive component to your future pnumatic tool collection, and your abilities will revolve around the compressor. An impact wrench takes a lot of juice to keep running.
PS: Those little yellow air cables that come with it....crap. Buy a decent air cable, it makes ALL the difference in the world on how your tools will work!