I've had mixed experiences with Partszilla. When things go well, their parts prices are among the best I've seen online, although their shipping can be on the high side.
When things go poorly, as is the current case, they list parts with a delightful "Ships in 1 - 2 business days" notice on the item page. Weeks later you inquire (digitally) why your order has not shipped, and a few days after that you get a reply that a) they don't have the part in their warehouse at all and b) they have no idea when they'll receive it. For what appears to be a large, professional business, that's pretty poor communication. Their payment processing, on the other hand, has no such issue.
There may be worse experiences out there, but right now I'm finding it tremendously difficult to recommend Partszilla.