Well, 7 years ago it was a $3500 machine: http://web.archive.org/web/20110901000432/http://pinside.com/pinball/forum/topic/afm-vs-tz
There are too many TZs for it to ever be a 10K machine, imo. I think there are like 2300 pinsiders with TZ in their collection. That is pretty close to number one from what I've seen.