Unlocked blu ray rom drive

I am in the process of building a HTPC and the last thing I have to pick out is what blu ray rom drive to buy.

 I live in the usa but a large amount of my store bought dvds are from all over the world so I need a blu ray drive that will be able to play any disc I put in it from anywhere in the world, for both dvds and blu rays. 

 So what is a heavily supported ROM drive by aftermarket firmware updates, to be able to fully unlock the all region capabilities?

Blu ray region restrictions are not controlled by the firmware in the BD drive in your computer, but rather by the software used in playback.

See here under Region codes: http://en.wikipedia.org/wiki/Blu_ray

You can use AnyDVD HD in the background to remove region codes for both dvds and Blu ray movies.