whats the definitive dvd of this to get? i don't think its ever been released in the us, but is there a dvd that has the full/complete movie?

Have you checked dvdcompare?

Bullet in the Head

It lists most (maybe all) of the current releases of BULLET IN THE HEAD. Joysales or perhaps IVL look the way to go.

Just to note, Dragon Dynasty has the rights to Bullet In The Head and they seem to be committing to releasing all their John Woo titles. Nothing's definite, but I'm also on the lookout for a definitive Bullet In The Head DVD and I'm waiting to see what Dragon Dynasty comes up with.