Newgg is great. Just be sure you're buying from Newegg direct and not a reseller from their "newegg marketplace." Like Amazon, the resellers can be shady scammers who sell fake crap or refurbs posing as new. Things to avoid from resellers: flash memory, SSDs, hard drives, laptop batteries.
They are not customer centric, so if you have problems you'll have to pick up the phone push them to do what is right, otherwise they are just as happy letting you pick up the slack. I try to buy from Amazon first, then if I must Newegg.
i also prefer amazon for their excellent returns policy, but newegg is also one of the biggest websites for pc parts.