The UK's Intellectual Property Office (IPO) has published a pdf that claims to "bust" the myths around this legislation. It seems that in order to use an orphan work, the prospective user will have to obtain a license to do so, and the process involved in doing this will be both complicated and more expensive than going direct to the owner in the first place. Full details are on the IPO's site:
As I see it, there is a change, but the effect is similar.
If you click on a topic with entries that you haven't yet read, at the top of the page, next to the "Reply to this topic" button, is a link labelled "Go to the first unread post".
Admittedly, this will mean that you have to open page 1 of the topic rather than going direct to the first unread, but the net result will be the same. Why has this happened? In truth I have no idea, but would assume it is to do with the updates that IPB put out. Since we were hacked last year, we have been super paranoid about not updating!
I actually find that shooting over/unders with 45° viewfinder is a pain as the water gathers in the eyepiece.
Saying that, I am sure you can probably removed the rubber cover around the eyepiece-I am just too scared to do so.
I have been fortunate enough to have used a wide range of housings (not for the 1 DX I should add) and find that the quality of materials and manufacture is overall very high throughout.
My suggestion would be to contact dealers close to you, or some of the excellent Wetpixel sponsors and advertisers, and get your own hands on the housings that are available. Any advice that is offered here will always be tinged with what an individual likes/wants from a product and there is no substitute for handling them yourself.
Shooting a SLR underwater will always result in a high level of task loading. In my experience, the only way to mitigate this is time in the water. Whilst over/unders may seem like an easier option, I think you may be surprised at quite how difficult they are to shoot!
Good luck with your search-you are lucky to be looking at housing such an amazing camera.