NewEgg is a no-brainer for most things. For example, I ordered a case from them on 12/22. Not only was the case an excelent deal at $50, they shipped it for free, and I had it on Christmas eve. This is during the busiest shopping week of the year, folks--two day turnaround from another state. Outstanding. That said, I've never had to use their customer support.
Bottom line, on 90% of the parts I buy, Newegg is the cheapest, shipped. They ship faster than any other online company I've worked with and I'm informed through the entire process. They ship via Fedex, which is a big plus, and display individual item shipping rates right next to the price. I am to the point now that I would pay extra to use them. They are just that good. I couldn't even make a suggestion on how they could be better--they can't be. They are the only company that I suggest to my friends that they should use (not just retail--literally for any product). Newegg just rocks!