The Region 1 disc was released a little while back and a SuperBit version was also just recently released. I'm comparing the Region 4 with the non-SuperBit version, because that's what I have. It is quite similar to this one, even down to using the same photo (with different text) on the front cover. The extras are the same, including having just the one commentary.
The Region 1 disc is missing:
The Region 4 disc is missing:
The SuperBit version of the R1 disc has a dts soundtrack, but no extras (that's normal for a SuperBit disc). So you can get the equivalent of the Region 4 disc, but only by buying both the Region 1 offerings — that makes the R4 disc look very attractive, wouldn't you say? The only drawback is that bad layer change. The R1 layer change is at 53:21, and near invisible.