My logic falls along these lines:
• Most Apple refurbs (from the Apple Online Store) are from the retail stores.
• Apple computers are allowed 90 days maximum in a retail store
• Apple generally replaces any part that is scratched.
• Apple includes all brand new accessories with each refurb.
I look at getting a refurb (from Apple) as like getting an extended warranty - the unit has been thoroughly examined. If it was in an Apple Retail Store (as most refurbs are) then it most likely is 3 months old - therefore ... it's kinda like getting a 15 month AppleCare warranty.
Also, I take into account that even the occasional NEW Apple computer could fail right out of the box - so what's the risk?
Apparently the same isn't true for Dell.
As reported by The Consumerist:
Ever wonder if "certified refurbished" is just corporate doublespeak for "not entirely broken crap?" Well, at Dell, it is! This refurbished Dell Studio ... arrived with large scratches and a CD-R in the optical drive containing a pirated copy of Microsoft Office. Dell's response? They're willing to take back the laptop and waive the restocking fee, but that's it.