Well...
One thing to think about is if in the rare instance you have something go wrong with your Z, you want to have someone in Japan or 'connected' to Japan (if you bought a Japanese market model) who you can send it to and rely on them to get it serviced and returned to you.
Knock on wood, luckily haven't had anything go wrong with my Z's, so haven't needed to test this out....but I do feel comfortable that Conics would take of me if I needed it.
Just my 2ยข....
Mark
Waiting Impatiently for SL-3000