I have owned a Vision SLR preamp for over 6 years. I asked Frank to put in 2 phono boards so I can use them for 2 turntables without swapping cables. For now I have only used the MM input on both boards. The MM phono is acceptably quiet but you can hear its internal noise with your ear less than one foot from the speaker and no music playing. My phono boards have the older chips (Burr Brown I think); the new Linear Technology chips may be more quiet.
The Vision preamp sounds transparent, at the same time non-fatiguing with beautiful tone in reproducing string instruments. In my system the imaging is good but not outstanding. It creates a wall of sound which is not very deep but not forward in your face. (I don't like the latter.) It replaced an old PS Audio 4.6 which is more colored in active mode. In passive mode the 4.6 is very neutral but is rolled off at both ends. The Vision definitely sounds much more refined than the 4.6.
Phyiscally the preamp is very attractive. I have the black version in the classic Van Alstine style; I like it better than the new, more luxurious silver version. All controls are very smooth, absolutely quiet after 6 years. The metal case work is very well done, as good as anybody's. Even the IEC power cable is very thick, more like one that comes with power amps. I know a generic power cable doesn't cost much, but it is not always a given that high end electronics come with a large gauge power cable.
I don't have the opportunity to compare different preamps in my system. But I go to concerts regularly (mostly classical) and my system is a good simulation of the real thing.
At the time, I wanted (and still do) a traditional preamp with built-in phono (don't want to mess with even more components and cables than I already have), tape loop (I plan to restore my cassette deck), mono switch for my very small collection of mono records. There were not many choices, even if you considered much higher prices, and there are probably fewer now. The fact that I can choose to put in 2 phonos is really the icing on the cake.
From my experience with the preamp and what I read about other Van Alstine's components, I think their own discrete SET stage is world class. It doesn't get a lot of press for whatever reason, but I kind of enjoy it because I have a fairly rare piece even among audiophiles. (I know this is not good for Frank's business which is not fair to him...)
