I have one, bought back in the day but never used. I'm very happy with the original Hasselblad finder.
There are often moments when straight view simply does not do for hand held shots, when low angle looks just plain more interesting. That is pretty much impossible with Hasselblad finder to do. I'm not bothered all that much by the silly distortion it shows, got used to it after a few rolls of film, so the superior performance of Voigtlander in that's sense was never my main point, if at all.
But my recent "discovery" that original finder does not have correct crop shown started me on the Voigtlander. Since I am getting one that will require modification for square format, I will be able to get the lines in the finder much more precisely to leave the guessing out to a lot higher degree.
Is this all worth it? That is surely debatable. But I know I cannot go low angle with straight finder, and that was enough, along with half decent price tag, to pursue. And if I don't like it as much, I should be able to stick it back on the market without any loss.