In my opinion, it's not even close: the color of money wins by a country mile. You have the best nine ball player ever versus the best all around player ever, both in their prime. They played at an extremely high level throughout the tournament (I don't know the actual stats, but I'd be surprised if they weren't both shooting above .900), and you had the classic "come from behind" story where Efren overcame a 17 rack deficit on day 3 to ultimately win. You could flip to virtually any rack of the 237 they played and see some amazing pool.
Mika vs. Shane... neither player was ever in their top gear, although Shane certainly opened up on the final day. But there was just so much sloppy play throughout the race. Don't get me wrong, I enjoyed watching two champions go at it, but in terms of the overall quality of play, it didn't come close to the color of money.