First off, Santana said that carbon disc forks are not a good idea with road tandems: http://santanatandems.com/Techno/MechVsHydro.html . I'd actually considered the Wound-Up/Co-Motion disc fork until I'd read the Santana comments. One of the Co-Motion forks -- the earlier one that you mentioned is/was manufactured by Wound-Up. I don't know to whom they farmed their newer fork to. YMMV.