Hmmm... I wonder if I should update these charts for the 1275 credit balls that are now being sold... the 975 credit one's are the most expensive I think I used before.
I have a quick formula to figure out approximate cost per stroke (putts on green excluded unless mulligan is used in practice).
2.5 durability ball (average 120 hits per ball, 360 hits per sleeve)
2.0 durability ball (average 100 hits per ball, 300 hits per sleeve)
formula (cost per sleeve / hits per sleeve) so that 1,275 credit sleeve would be 3.54 credits per hit.