I dig the wheelset.
I wanted to get them for my Silvertip but sold the bike already.
My FN Hon (2 screw top on left of picture is stiffer) and Dahon (quick release top) both fold down to the left of the frame.
Pics show the Tern post folding left, these are probably the stiffest but I have never seen them sold anywhere.
I think any of the 3 on the right of your picture would be a vast improvement on rigidity over the crappy 2 piece handlepost.