Marketplace
PAMPER20
You normally wouldn't see me recommending a 1700x over a 1700 due to its poor default overclock at the typical pricing, but in the case of a 2700x vs a 2700, the overclock setup is perfecto.
So you're getting slightly better quality silicon, great factory overclock out of the box, for $20 more than the best price on a 2700 (or $10 compared to standard retail pricing). This also compared pretty favourably with some of the standard overclocks you'd see on an i7-8700k.
For your individual needs and use cases, seek benchmarks that give you a direct comparison. For example, if you earn a living off Adobe Premiere, an 8700k is the vastly superior choice right now given how Adobe have chosen to optimise for Intel iGPUs.
One caveat: Futu can be dicks to deal with when it comes to returns because they are always looking to play the eBay marketplace for the highest possible margins at any given time, and as a result they (at least until recently) loved to fiddle around with their stock listings, IDs and prices. If they consider this price to be unfavourable to them, from my own experience they will make life hell for you if you get a faulty product out of the box under these circumstances, as they will push the letter of TPA law (and beyond) in order to force a refund.
I've contacted the ACCC about this previously, but in my case, as they eventually tried to offer a token gesture of an inferior (but technically similar) product as a replacement, this was apparently seen as not worth pursuing under ACCC guidelines. What worries me is that if you escalate with eBay, they will attempt to withdraw any form of recourse other than a refund via PayPal, which is technically illegal in this country. YMMV.
Nice find however your last two paragraphs are enough of a concern to make Futu a stay away store.