Some 2 dot balls are more durable than the 2.5 dot 120 hit balls. So the real cost can only be determined after counting the hits you get with the new ball.
BTW I find it annoying that that WGT does not show the hit count in the specs. It seems that every 2.5 dot durability ball has 120 hits. But for 1 1.5 and 2 dots there are differences in the hits you get depending on the ball type.
Update: The Callaway gets you 104 hits. So it is 15% more expensive compared to the usual 120 hit 2.5 dot balls. So its real price is 515 credits. Definitely overpriced for this ball.