There is a simple rule - I buy loads of mics, especially the fakes to see whet they're like - and the rules work like this. Buy from a legitimate dealer who offers returns. Online orders certainly in the UK and most places are protected - I must give every person who buys products from me a return within 14 days simply because they change their mind. In most cases, I lose postage out, and they lose it coming back. I am NOT s Shure dealer, or a dealer for any expensive brands, so when I buy Shure SM58/57 or AKG or Neumann I buy from an authorised dealer or reseller. My couple of year old U87 came from Thomann in Germany - and was a B stock. The box had clearly been through the postal system, but the mic is as new. My AKG 414s and Shures come from the same source. All Shure mics are the same price from all authorised dealers, with a maximum of maybe 5% difference in price and maybe free postage thrown in. That's it - if you see a 58 (in pounds) you will spend at least £95. If you see anyone selling a new 58 for £60, it's a fake.
Some of the fakes are extremely good - some of the 57 and 58s on the market are indistinguishable from a real one in a side by side test. Others are dreadful - but look the same. The current iffy one are SM7Bs which again sound to my ears exactly the same, but others are poor. I cannot tell the difference between a genuine one I have and a fake I bought. There is no difference to my ears and I had to stick red tape on the fake, because if I mix it up, I am stuck. I have some Neumann handheld fakes. None sound like the real thing, but one is close and better made. The others have poorer construction so handling noise is bad, but so is electronic noise. I bought three 'U87' mics - two were the same body with different electronics and one was totally different. Quality went from awful, to usable.
What I do know is that there are two things for you to consider when buying mics like this, where there are fakes on the market.
Morals and Ethics - if you buy one, knowing it's a fake, and can live with it - then some for little money are very good. Not as good as a real one of course, but perfectly usable. Buying one to sell is totally different - that for me is totally out!
The other is price. My U87 was with a proper VAT receipt, so to me the cost to my business was £1500. That is still a huge amount of money, but livable with. If I saw it on ebay, or Amazon for a grand, I would NOT buy it - too risky. Current model, high price products are not that sort of price. Vintage of course are totally unavailable for cheap prices.
What is absolutely certain from the dozens of mics I've bought, is that a few are dreadful, most are usable, and some are actually quite nice. As an example - there are quite a few TLM103 mics on sale. All produced in China - and some have a 34mm capsule, some have a 24mm one and oddly, they're not too bad at all. My ones came with little Neumann badges you could stick on - but a cheap plastic iso mount. My real one is much heavier and sounds better to my ears - but a pair of the 34mm ones would be great for piano, or as a stereo pair if you were short of money.
I've just bought a fake Audix D6 - it's not arrived yet, but I bet it will be a plastic case, not metal, and not remotely the sound of a D6 - which to me sounds a bit like a 112 - my favourite. I'm planning to try a session with a double bass with it. I know a kick would be better, but transient sounds seem to rarely allow good comparisons - because it always sounds either click or mellow, so an instrument should make a better comparison and others have done kick drums with different mics and I struggle a bit.
I do NOT always damn these Chinese fakes - they're producing what people want. Cheap mics, and while measuring mic grills sort of works, it means very little. Nobody buys a fake when they can afford a real one. Lots of people simply can't. Worse - some mics just sound good. I remember buying two Roses when they first came out and I really liked them. My favourite AKG414s get used for everything because they work on almost everything. My U87 rarely gets used, because it is not as magic as I believed. It is really nice on my tenor sax, and I don't use it on the alto - it's too thin and shrill. It is nice, but not wonderful. I thought for the money, I'd be really enthusiastic but it's just, well, nice? I've used it as the side mic with my TLM103 which match really well, but frankly the issue with it for a mic bought with personal money is I need to keep it pristine and kicking the stand over, or tripping over cables is scary. The 414s have proven to be really tough and both are marked and the grills nearly un-dented.
Some fakes are truly awful, some really, really nice - some people are offended by the idea of fakery. Others will happily buy a fake Gibson or Fender guitar. I know all the legal arguments and the hatred of counterfeits I do get - but I can live with it, hence my search for decent ones. I've linked in one of my videos but you will find loads comparing all sorts.
