Just had an unbelievably difficult time with the ebay store called fastsource_autoparts.
Slow shipping. Received the wrong parts TWICE, which put my car out of action for 3 weeks. Still battling with getting a full refund.
They do offer better price that auto zone or other online stores (maybe by $10-15 per caliper), but for the hassle they put me through, I would not buy from them again.

Ended up purchasing a refurbished brake caliper from Autozone (online). It came in the very next day and worked like a charm. Easy core return at the store.

 

Try RockAuto next time, Centric(Stoptech) Reman'd calipers turn out to be about $200 for all 4 corners before core-exchange.