Someone sent me a PM to post here about AliExpress. I'll cover some of the stuff mentioned above.
1) A good deal? Certainly for Chinese stuff. Definitely not for European stuff - you CAN get Andro, Stiga stuff etc. but it's often MORE expensive than European stores. I do like that all packets are tracked, I've not lost any table tennis stuff in the mail. Here, untracked packages usually just disappear (someone at the post office steals them). It does take 3 weeks or more to arrive, of course.
2) Genuine items? Depends on the items. If you see any Butterfly Viscaria or Nittaku Violin blades for $20 those are most assuredly fake. On the other hand, that Sanwei M8 blade (my favorite) is most definitely real. I mean, what's the point of counterfeiting a $8 blade?? (Though I have come across counterfeits, er, copies, of cheap 80 cent model gliders.) I did order a fake Butterfly Primorac blade in the past (only after they put it on discount for $8) - it played OK but I've no idea what a real Primorac blade is like so I've no idea if it was anything like the real thing. Similarly, I bought a fake Tenergy 05 (again, only after they dropped the price from $16 to $7) - THAT was unusable. It was literally like fast anti. Don't know what they were thinking - I was expecting something like 729. The fake blades and fake Tenergy seem to have disappeared over the last couple years, and you'd NEVER find them at the "good" stores. One thing though... NEVER NEVER NEVER buy memory products (USB drives, SD cards) on AliExpress. It's GUARANTEED you'll get a fake one.. usually a "64 Gigabyte" one that takes about 500 megabytes and then the rest of what you store is corrupt. I went crazy the first year and bought three or four on a 11-11 sale. On the bright side I got ALL my money back. It seems they'll side with the customer if you file a complaint.
3) Specific stores? The "go to" stores are the ones set up by Eacheng (of eacheng.net fame). Most of the stuff I bought came from these. Last I checked, there's SEVEN of them. If you search for "Yinhe 9000" the stores that sell the 2-in-1 generic packs are Eachengs. Note the prices are all different.. it pays to search for the item to figure out which store has the best price. To complicate things even more, Eacheng runs two accounts on ebay (China Friend, and another I can't remember - they sell more or less the same stuff) and they're also on Amazon. I think they're also on German ebay, French ebay, etc. with different accounts. It's all the same company. Everything they sell is genuine - but what I love is the non-standard or non-official stuff. Those 2-in-1 packs of Yinhe 9000 for instance. Or 729 Super FX with the large pore sponge. And they've got some really weird, obsolete stuff, a lot that are no longer ITTF approved, or were too early to have an ITTF logo. Most of these are OX pips sheets - for example Yung 63-9A with the mushroom pips. And some obsolete Hallmark and Avalox sheets. I don't know if the Hallmark sheets are frictionless - I've heard the real thing were treated at the factory by coating the tips of the pips with epoxy and these haven't been treated yet. As to the stores mentioned in the original post - I've no idea about Selective, never bought from them. But Burn and BEO seem OK - BEO always has the best prices on DHS D40+ balls (I like the 2 color ones by the way). The other store I've bought a lot from is XVT (two stores). Can't vouch for all their stuff, but it seems OK so far. They have a LOT of own-brand and weird brand blades (and a good price on the M8, so I've bought a number of those from them). I've also bought a small amount of stuff from China Ping Pong and Playa. Also seem OK. Playa sells something interesting - custom blades for $75 and down. You get to choose the wood from several choices (e.g. Viscaria, Clipper, Inner ZLC), the handle pieces, decorations, and you can even get your picture on the butt of the handle Ma Long style. No, I've never tried this service. Look under "DIY TT Rackets". They also sell some questionable stuff, namely "Chinese national team" specific "personal rubbers" (of Ma Long et al.) and most interestingly one of Ma Long's personal blades (they want $2,500 for it..). Some of the smaller stores are "siblings" - like the Eacheng stores, they're actually set up by the same company or same people, and you can tell after comparing them. Can't remember any at the top of my head, but I'm pretty sure I've come across at least two or three cases.
Iskandar