Get the biggest one you can afford. I'm serious. If you break apart the cost of the air tools included with the set, you'll find that they really are hardly discounted much. Plus you can get a set of air tools (even as a whole "set") apart from a compressor.

Some air tools will run forever on a little five gallon compressor. I'm sure you know about comparing CFM/PSI ratings on air tools. Look at the biggest thing you're going to (ever) use. If you're doing paintwork, look at what KIND of gun, and then step up above that. You'll be very happy you did. There's nothing worse than making the final pass with a spray gun while running out of air. But if you're only doing OCCASIONAL use with the compressor (periodically an impact wrench or a drill or something) you won't have to worry about letting it catch up now and again.

Also note that to step up to a BIG compressor doesn't cost a whole lot more.
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1992 940 wagon, very low miles
as well as others.