The UK version should be a bit cheaper for those of us in the UK - but I dare say more than a few people would rather pay the extra quid or two for that prestigious Criterion sleeve....
Given that the Criterion is more or less extras free (other than the trailer and a weird sound-less doco hidden away as a VOB file), the significant cost saving for the R4 will probably make this the version of choice (although I will wait for a review of the transfer before leaping)...
AFAIK the sound on the criterion is 2.0 "only" maybe we are more lucky and get a 5.1?? anyway checking the prices the UKR2 will be around £12.99 whereas the criterion is around £15.99 for exactly the same disc. (not considering that dodgy easteregg) Then again Criterion discs have something special...the name in fact.