if we're talking toj0, i'd rather go an inch or two too long on the sleeves than too short. the ribbing will make it fall exactly where you want it anyway and nobody is gonna care if your sleeves are on the longer side because the stacking effect looks pretty cool. when i see varsities where the sleeves end an inch before the wrist it looks uncomfortable and dorky to me - imo.
i'm 5'10" and i always go with 48 lengths. 46 falls exactly at my wrist but as soon as i start moving around it hella rides up and starts bugging me.