I got me a genuine e3dv6 from them directly (they have an Amazon store so you can trust buying it from Amazon if necessary though.) The (seemingly) excellent knock off is here https://smile.amazon.com/dp/B08R99BBRS/ref=cm_sw_r_apan_glt_fabc_5RTWVBTHV2T4PZN11EF2

I actually ordered one a few days ago for possible testing purposes... and for the inevitable day a print fucks up so badly it encases the hotend in plastic, which is what happened to my OEM cr10v2 hotend & enclosure.

The positives are pretty extensive, but I'd say the big ones for me were a good doubling or more in printing speed at most any given quality and more or less infinite bridging ability (my test model topped out at 120mm or so, I didn't bother testing further.) Mind you, this is with the herome 5015 fan double duct enclosure, so there's that confounding factor.

But it also allows you to print with real quality materials, like nylon and ASA. Oh and the nozzle type is far better for ironing, among other advantages.