I'm starting to think that the current generation of employees at Progressive aren't exactly on top of the situation like the old timers were. I realize that H-D doesn't do a lot of things with an eye toward making life easier for the aftermarket guys, but it shouldn't be all that tough to keep track of what the standard shocks are on the various models.
The CUSEx comes with the same standard shocks that come on the regular Electraglide models like the FLHTCU. So that means a 13" air shock, and changing to the Progressive 13" 440 won't change the ride height. Going with the 944, on the other hand, will lower the ride height when the sag is adjusted as per their instructions, even though the shock measures 13" fully extended. Slight-of-hand involved, and not the best solution if lowering is your objective IMHO.
Jerry