I was rather reluctantly dragged along to see this today, but ended up enjoying it.
It did feel a bit "twilight" in nature (i see some disagree, but it's clear from the lead cast it's going for the same market), but it was saved by having a smart script and by virtue of not taking itself too seriously. I thought the use of a monologue from the internal perspective of R was a good concept well executed. A few deft editing touches and an interesting use of music also add to the films charm.
Main draw backs were the cheesy ending and the almost criminal under use of John Malkovich
7/10 for me.