I guess it all depends on how much you use it when you check refurbished electronics... Most people probably use the PS3 for few hours a week and they think the refurbished unit is fine. However, if you sort of abuse it a bit, things might be different...
Anyhow, it's a good deal, but the reviews are not very impressive (referring to the refurbished units at Cowboom). Here's a coupon to knock another $10 off.
EBates10 and 1.5% CB
FatWallet10 and 2% CB
new customers only (both coupons)
I think I'll wait for another deal, trying to get a 3rd PS3... The 2nd one is dedicated to movie/netflix/casual gaming now.