Preferred Barfly as a film, but Dillon is pretty good as Chinaski. I actually thought Rourke was decent, anyway. Dillon perhaps edges it on the run down, cynical, man of the world bored of it all score, while Rourke has more humour and free spirit about him that I enjoyed.
I get the feeling Buk would've found fault with anyone playing him (/his alter ego) because it was such a personal thing that nobody could really quite pull it off, without actually being him. Am about to watch "Crazy Love" by the two Belgian directors, which was well received by Buk (think he said something about their ending being better than his - "hey why didn't I think of that?" - in a documentary) - perhaps partially because Chinaski's not in it...?