Hi David
I've just been through the same process: owner of a D100; and user of CP5000s with a Subal housing for underwater. After much thought I sold the CP5 housing at the end of last year and bought the Subal D10 housing for the D100 - and am delighted with it. SO much so that I have bought another D100 so that if one packs up - or becomes unavailable - I have a second.
Yep, I read Alex's reports about the D2X and the Subal housing and, being male, think, yep, gotta have one of those..... and maybe I will when they are old and the price is coming down. Who knows when the D100 successor will appear.
I can understand your concern too about servicing when you live in TCI (lucky you). As you may have seen through other posts, the Subals are superb: high quality and well built. After about 100 dives my CP5 only had the slightest of scratches on the case - and worked like a charm: which is more than I can say for the CP5s sometimes.
Get the Subal D10 you won't regret it. It will withstand a hit from a tank round - and as I now live in Kabul that is quite handy.
If you run into Cynthia Astwood in Grand Turk say hi from Tim formerly of Bermuda. (Yeah, yeah, I know, who did I upset...)