Blu-Ray that sell out - become rare

[Blu-Ray Winstone]

I'm new to this site/forum so don't shoot me down for this..... I have kinda posted this question on Pulp Fiction Steelbook thread.

I am surprised a movie like PF, on an exclusive to Play.com only Steelbook hasn't sold out.. Just because of steelbook collectors on top of movie/blu ray collectors. It is a massive film to have only just been released on this format and the transfer has been overseen/approved by QT himself.

I preordered XMen First Class steelbook, that releases 31st but sold out from pre order days ago.

Just wondered what fellow collectors here thought about how to spot a release which may turn out rare or out of print ??

I missed out on Back to the Future tin, thinking it'll come down to £20 or less in an HMV sale a few months later.... WRONG !!