I don't agree that the price of the game "can only be answered with the money paid for a pinball machine taken into perspective". It is just one factor, and perhaps a big factor in many cases, but I find it difficult to accept opinions expressed in absolutes like that.
For example, while Big Bang Bar is extremely expensive and is **not** the greatest game play of all time (but likely among the most expensive games), by a pure cash definition it would be over-rated, because there is possibly even a Sega (like SST) that might be a better player depending on your tastes. But it's high price is a function of a number of factors - rarity, fun gameplay, unique and extremely well executed theme, unique layout, unique toys, great sounds, brilliant artwork.
I think these discussions are really interesting as it helps me think about other games.
I like some others dislike TZ, and owned and restored one before coming to that conclusion. But is it over-rated? Absolutely not, because its fun-factor is appreciated by a large proportion of pinheads, who must like the more stop-start style it has (and which I do not like) and its incredible array of toys and superb tie in to the series.
