Mem11:
Not quite - GI2-SD2(Legend Ball) has 1.5 Dots of Durability. The New Callaway Tour i(s) has 2.5 Dots of Durability. That's equates to a 67% increase.
I have serious doubt about the Durability. 2.5 dots may not mean 2.5 times more hits than a 1 dot ball. This may not be accurate, but I counted 90 something hits for a 1 dot SD ball and only around 110 or so hits for 1.5 dot legend ball. Again, I'm not good at counting, and may be completely wrong. :)
Wgticon, could you please tell us exactly how many hits each dot means?
Or, someone good at book keeping please track the number of hits and post it here. Any shot except putt counts as 1 hit. According to wgt, the durability meter turns red when it reaches 25%. So one can just count how many hits after it's red, and then multiply by 4.