Of course you can. Newegg tests them before they put them back up for sale. There not sold as faulty parts.
I go one step further and buy parts listed as faulty off eBay all the time. 75% of the time, the seller just doesn't know WTF they're doing and I end up with a bargain. Just the other day I snagged a couple of HD 4870 X2s for 60 euros, both work perfectly, you may have seen the thread.