I am not going to mince words or dance around it: this is an Abaddon model. This is Abaddon the Despoiler wearing his Terminator armour armed with Drach'nyen and the Talon of Horus. Its Abaddon. Officially, of course, this is the Chaos Master Of The Crusade from Grimskull and sold by Wargames Exclusive via their eBay store. They're a Ukrainian company and so IP rights can go hang.
(Actually, funny thing, one of the eBay listing for this model was simply titled “NotAbaddon”).
Let's address the moral gray area here: there is an existing Games Workshop Abaddon the Despoiler model. It is, however, awful. Its old, its chunky and its built on a smaller scale than almost anything you're likely to stand next to it. Its only selling point compared to the Grimskull version is that its cheaper (£15 against £26-ish including postage and packing) and quicker to acquire just because of distance.
But I just don't want it. It looks awful. I don't game much in GW clubs so the blanket (and understandable) ban on third party miniatures doesn't really stand to inconvenience me plus the local GW club has a 1000 points / 50 power army limit so I'd likely not use Abaddon there anyway. The fact that this isn't an official GW miniature doesn't inconvenience me in any immediate sense other than the fact it took three weeks to arrive.
And, finally: capitalism is not a moral system. It is not my job as a consumer to put up with an inferior product for the benefit of Games Workshop. I have no doubt that if GW decided to replace their Abaddon model it would be superior to this; made of plastic with a greater selection of options; have the right iconography sculpted on; been usable in club environments should I choose to; and, more convenient to buy. If that model existed, I'd have probably bought it even though it would likely have weighted in at £5 to £10 more than the Grimskull version.
They did not provide that option. My money went to the Ukrainians. That's capitalism.
Now, obviously, I can't argue that Grimskull are in the right in making and selling this thing. It is obviously Abaddon and that's IP infringement. If and when a GW lawyer braces the oblast to serve a cease and desist... well, you pays your money you takes your chance. That is also capitalism.
And I got a good Abaddon out of it, that's all that matters.