If your refering to the lovejoy style couplers, I will be using them. The main reason being is I will be using 1/2" acme thread leadscrew instead of the 5/16" all-thread rod.
I wasn't sold on the whole rubber hose idea when I got the plans anyway. It just seemed that way has to much potential for error in alignment.
I will be ordering the couplers from enco:
http://www.use-enco.com
Trevor