Nice review, with nice pics too.
I picked up one of the TW "tank adapters" and use it on my SD MKII. It's basically a slightly longer version of the standard 901 to 510 thread adapter. It came with a cone shaped tank atty and cart. I mainly wanted it to use my cache of XL/Mega/type B eGo attys so that they wouldn't go to waste. I didn't think I'd like the tanks, but have to admit, the one that came with the adapter has been working remarkably well for a couple of weeks now. The cone attys (tank or regular) seem to look nicer on the SD than the cylinder types IMO.
One thing that I noticed, the Trog SD looks like it has an unsealed connection. Is that correct or is it just the way it looks in the pic? I'm not too hot on the unsealed (open hole) connection on the TW adapter and was figuring that Trog would use sealed types on his. At least the SD MKII has a sealed center post although I'm suspecting that the atty connection assembly (top cap) isn't entirely sealed as I have heard of leak issues from other users in the past.
I still don't have an original Trog made SD, but would like to get one of his gold/copper colored ones. Much rather have a UK made device over a Chinese made one.