On the '04 I think 20's, '05 and later 22's. Regardless of what year the bike is, it depends on the type of riding you do and how aggressive you want the front end to track.
the triple clamp offsets on crf250/450 r/x models have all been 24mm until this year with the '08 models. during this time honda has adjusted the front axle location back 2mm essentially creating a 22mm offset.
it is correct that offset affects steering quickness so depending on what type of riding you do and your skill level will determine what offset is the best for you.