I have the SV F50W2 fitted into a Takahashi bracket, it is a beautiful finder, I have used it with various Vixen LVW eyepieces as well as the supplied 23mm.
Very good optically, the helical focuser on mine is quite good in that it does not creep as some others have reported. The diagonal can be rotated but there is a small change in alignment when rotating the diagonal.
http://i13.photobucket.com/albums/a2...ps26fa6ef9.jpg