Newegg

Usually very reliable. They seem to be adding many new non-computer categories via the "marketplace" style third-parties. Not sure I am a fan of this. My experience with these types is so-so at best. Seems most are Chinese based sellers who seem to exaggerate the functions and quality of their products (to put it nicely). So what if you can save 30% off on a tripod if the damn thing never works!
In regards to newegg.com themselves, they are great for any laptop or desktop computer stuff you need. I just advise being careful with the third party sellers.

Never had a problem getting my parts from them even though the shipping was sometimes a tad slower than desired. The times I've needed to make a return they always accepted valid merchandise back no questions asked.

Only issue is they're always out of stock and overpriced on new graphics cards. Hard to complain about much in my experience otherwise.

This is one of the better electronics sites out there. I ordered UPSs for work. They arrived in 2 days with the free shipping option. Awesome! Well packaged. Items just as stated.
Maybe not the cheapest but close. Barely higher than Chinese based companies. If you don't want to wait 6 weeks+ for stuff to come from China then I highly recommend Newegg.

Update: I have reviewed newegg.ca only. I cannot speak about newegg USA, Singapore, Australia, etc. I recommend that buyers look for specific reviews on those.

Have been buying from Newegg for at least 10 years. I find they have consistently good prices, a nice variety of products, quick shipping, and very little need for customer service because they get it right the first time. I've spent thousands at their site, along with others, and they currently lead the top 3 or 4 that I buy from. My experience with them spans memory, motherboards, hard drives, SSDs, power supplies, video cards, and miscellaneous boards, keyboards, mice, etc. I refurbish computers at a local community center for donation to needy families, so the need for low price and high quality is always on my mind. Good shop to do business with.

A hacker ordered stuff from my new egg account. I was able to act quickly and cancel all items except a 99 cents gaming code. New Egg would not refund. Instead they want me to go to my bank which would result in my credit card being reissued. This is a huge unnecessary hassle given that my credit card info was not exposed. This just shows how petty and small minded New Egg is. They don't care about their customers and everything is your problem. Suffice it to say they have forever lost a customer over 99 cents. New Egg should really think about using more of Amazon's customer service practices if they want to build their business. Trust and perception are everything online. So lame to throw that away.

This company will be a continued source of my shopping needs. They are always willing to help out with your order and questions. Just recently something had gone wrong with my order. All I needed to do was call them and, without hesitation, they fixed the issue perfectly. Great customer service and great deals too!

I bought the 5700 XT from Newegg and I was having minor problems with the card. I didn't want to take the risk of more problems so I try to return it. I heard the GPU have driver issue but bought it otherwise since some people say they didn't have any problem.It cost a big whopping $60 stocking fee for having the item for like two days. They don't even pay for shipping to send it back so you have to pay for that too. I also read that some people say Newegg didn't even accept their returns. If you do buy from Newegg, make sure you going to keep the item or else it will cost you money! Otherwise go buy somewhere else like Amazon. I return stuff from there before with no stock fee and got my full payment back!

Been customer since 2004. Had to argue for 25+ mins for free RMA. Bought a lot of item from several sites. Dont often RMA products. Did not realize there is RMA fee and shipping fee. No going to waste another 25 mins for waiving shipping fee. If companies can offer no questions asked 90 free returns. Dont understand why online company that does not have actual stores cant even match similar service. Not to mention so many rules. Done with Newegg.

I'm never ordering from these guys again. I received a non-functioning product, so naturally I try to return this item. Originally I wanted to exchange for another, but noticed it is now out of stock. So then I go through the return process. I get my shipping label no problem, and send it off within a few days. When they received my return I got no notification whatsoever ever from Newegg. The only reason why I know they even received it is because I'm tracking it myself with UPS. It has now been NINE days since they received my return and no refund still. I find this unacceptable for this kind of business. They have lost any business they were going to receive from me and I will highly recommend anyone I know and care about to never do business with Newegg either. Never again will I be making this mistake of transaction

They false advertise their non refundable products then when you realize it's not the product you wanted they throw their no refund policy in your face and make it look like it was your fault.

Edit:
I noticed a lot of ppl here had problems w customer service.
I spoke w the Cust Serv representative (RJ) and his supervisor (Vin) for over an hour. They both lied about product description and were generally unhelpful. This is my first and last purchase with Newegg 0 stars