Just pick up an F2. That way you can still use all your existing Sinar components except those heavy geared standards. I backpacked for twenty years with one of these, though I have since replaced it with
a classic old Sinar Norma (no yaw-free asymmetrics). I'm not quite sure why you'd need to specify this
one feature, but the F2 does have it, though you operate it a little differently than on a P camera. If
you are comfortable with a monorail it's kinda silly to go looking at wooden folders. And no, nothing like
a 'Dorf operates in this manner. The Wisner is pretty flimsy compared to a Sinar - more pretty than functional if you're going to get into weather. If something goes wrong with a Sinar, replacement parts
are abundant. Try getting a Wisner fixed! The nice thing about a monorail in a pack is that you can leave it assembled with a favorite lens and shade already in place and operate much faster than with a folder. Plus if you want to use long focal lengths, you just add another rail section, same as the P.