Thanks for your informative review and commentary Canip! My impressions of the three models had many similarities to yours - eg. feeling a bit heavier than I had expected from such a compact binocular. The slimness of the eyecup rims was a detail I definitely noticed and ought to have commented on. Most noticeable in the 7x35, the slimmest of the three, the result is that what is outside your field of view is not as effectively blacked out as with (for example) the fatter eyecups of something like the Zeiss FL. Even though it takes away somewhat from the "immersivity" of the view, I don't completely object to it, as the increase in your peripheral vision can be a real advantage. The field stops are very clean - I would have to agree with the poster who mentioned Leica binoculars as having neat and perfect field stops - and I was able to set the binocular up so that the field stops were a long way out from the center, both of which help mitigate this effect. It's less apparent in the x40 models which are larger in diameter.
Eye relief - I found the Retrovids all had slightly more than the 10x40 Dialyt (nominally 15mm), as I needed to turn the eyecups out very slightly. I wear rimless glasses set close to my eyes.
CA - I must be relatively tolerant to it as I didn't notice it in all three Retrovids I tried, certainly not in the center.
I think the 8x40 is in a very competitive corner of the market - there are a lot of really good binoculars around now that weren't during the era when Leitz and Zeiss were the two great names. The 7x35 has less competition (most of the quality 7xs on the market being the significantly larger x42s) and is somewhat unique in being a quality 7x in a very small package. Although certainly not a pocket binocular, it's still compact enough to fit in a lady's handbag, and I could imagine that if the likes of Camilla Parker Bowles ever wanted a replacement for the Ross Stepruva (?) I recall her being pictured with, this would be the ideal candidate. The 10x40 is also in a bit of a separate corner of the marketplace, being so much sleeker than most 10x42s - I can't say I agree with most of Ken Rockwell's (in)famous web page discussing his Leitz 10x40 non-B, but I do agree that they handle and point beautifully. I can see the logic of Leica reserving them for their own stores, as the dedicated birder or shooter will almost certainly go with something else. They are really there for the LEICAMAN (thank you, Ken Rockwell...) who wants a pair of binoculars to go with his camera. I don't know how all that translates into a profit-making venture for Leica, or whether that's even the point, but I'm not really bothered about that. I'm certainly glad they are in existence - it would be nice if a 10x40 became available secondhand at a price I can justify in a few years...