I'm not really impressed with either one. Overstock is just barely discounted from normal prices, and ebay is just another store at this point. Outside of collectibles, I haven't seen a good deal on ebay in a couple of years.
For real. I used to get such sweet deals on ebay, and now it actually seems like I can beat the prices at a store.
Zappos is king though.
freemexicancocaine is an up and comer, too.
Zappos is teh AWESOME!
Seriously. Their customer service is world class.
Try this. Next time you need some info, like where a hotel is or something, give them a call. Any department. Ask them where the nearest hotel is, they won't even blink. They'll google it for you and give you the info.
I have their number on my cell phone for when I'm out of town.