Have bought a few things from them and never had a problem. Have never contacted their customer service or had to return anything so have no idea how they are to deal with. Buy almost everything from newegg because their prices are competitive and service outstanding
the two best sites online for buying computer parts that i have found are newegg and zipzoonfly. newegg was always better but today more people are buying from zipzoomfly because of the slightly lower price and freeshipping on almost everything. neweggs customer service is still the same as it always was and so is zipzoomflys both top notch. newegg has a much better website and userfeedback and product description. that being said if you type in say... pricegrabber and see newegg and zipzoomfly youll see 30,500 plus reviews for zipzoomfly and only17,000 for newegg because of a cheaper price and freeshipping.
yes zipzoomfly is a mirror image of newegg.com and to my knowledge its only competition. i have looked at tiger direct as i live in same state and the price is always more so i dont buy from them.
I have bought from Mwave a few times and they are good to deal with in my experience. I don't remember what I bought from them but I know that it was a good experience. I think I bought some DDR400 they had a while back.