Well I got the coat in today, and while I haven't had the chance to put it on yet, I wasn't immediately impressed. The tailoring and imitation of HT is extremely well done, but the build doesn't carry the gravitas of the HT one. While HT's is too bulky and not necessarily accurate, it feels of higher quality; things like the buttons are a step down for sure. That being said, I have to commend the OSK coat for it's accurate color representation, and how faithful it is to the HT one, down to the obscure holes along the bottom hem of the coat, as well as the torn toggle on the back flange. The thinner fabric is undoubtedly more versatile and will fold better at the joints, a nice bonus. The lapels are also much more clean and naturally scale compared to the heavy hem of the HT one. I'll have to put it on the figure to make a final call, and the pictures here do make me feel like it is the right decision to upgrade it.
Also a friendly reminder for everyone to keep an eye on the inside of the goggles - mine had a small plastic tab that has scratched the cowl. I've since put a small cotton pad over it. Just be cautious folks!