[Rocinante]

Porter cable has a 2 stage 15cfm @90. My local farm and fleet sells it for $800. No clue if it's any good.
IR has the SS5L5 single stage 18 cfm @90. You can get these for around 850-900.
IR SS3l3 is around 10 CFM and runs abour $600 I think.

I've read good/bad about Lowes units. Seems like some have had issues getting service. Kind of hard what to believe off a few reviews on the internet.

I believe KLF is correct, most of the cheaper pumps come from the same few vendors. Most likely the quality is similar.

I've been keeping an eye on Craigslist for a used Champion or IR or the like, but every time I see one for a decent price, its gone by the time I call.

Personally I would stick with the bigger names, my assumption is if it takes a dump you'll have an easier time getting parts then a lowes/HD rebrand.