Fair enough. Reckon you could purchase the Ultegra Triple tandem set, remove the 30t ring, use as a double with the new di2 Hydraulic Ultegra levers? Would need 11 speed chainrings? Or am I not thinking of something else ?!? Achieving tandem greatness seems difficult.
FSA stuff tends to get pretty poor reviews. Usually highly inflated RRP to make OTP bikes with cranksets look good value.
Hulsroy has had some bad experiences with pedal inserts, detailed here
https://www.lfgss.com/conversations/259306/?offset=150#comment12413106