All it is at the moment is a big nic-nac usable only as a conversation starter and space taker-upper in the shed. A mate of mine bought a NOS boxed 410 AJS Stormer a few years ago and at first it was a cool thing to show off to guests. After a couple of years he'd got a bit tired of it taking up the space of two bikes so he decided to put it together and ride it. Another mate bought a NOS '73 CR250 Elsinore from a collector back in the early 90's. He immediately started racing the bike and still does to this day. The moment that bike turned its first divot of dirt at Dargle, its value halved and it became just another Elsinore. Same with the AJS.
The downside of this is that whoever pays top dollar for the CZ may eventually go through the same situation as my friends did. Once assembled and ridden the bike becomes just another '73 CZ, if you keep it as is it becomes a very expensive dust catcher. Not much of a choice in my opinion.