I've also been demoing all the VSL Synchron pianos this week, and I agree that the Steinway D-274 stands out as being particularly excellent among the modern grands. I find to be very flexible and powerful, and it really responds to what ever I try to convey in terms of expression. Might be the best of the bunch all-around. It does sound a touch hard and aggressive at the higher velocities, and I still think I prefer the warmer tone of the Bosenderfer Imperial overall, but the Steinway is really, really good. I plan to purchase this once the trial period is over.
I also absolutely adore the 1895 Bluthner, which I purchased from David (thanks David!) but that is more of a niche instrument and probably not for everyone.
I didn't care much for the 280VC - it sounds rather hard, flinty and one-dimensional to me. Nothing at all like the Imperial. I would never have guessed these come from the same manufacturer.
Judging from peoples responses on other forums, the CFX seems to be the runaway favorite, but I personally don't find it to be all that special. There's nothing wrong with it, but I don't think it has any standout characteristics either, and just seems somewhat neutral and colorless to me in comparison with the D-274 and the Imperial. But I seem to be in the minority in this opinion.
Both the uprights are very well done, and convey the character of the instruments well, though I personally prefer the Bosendorfer over the new one. Actually the new 1904 German Upright sounds extremely close in tone to another VST I already have (NI Gentleman) which is also sampled from a turn-of-the-century Bechstein upright.
Maybe I'll post some samples later.