I like the snap on design. They made a wrench precisely for situations where access to a fastener was very limited and you could only turn it a small amount. A 15' angle didn't make sense for a wrench designed with this in mind as 30/60 angles are meant for situations where a 15' is useless and won't re-grab. 15/60 wrenches work fine in less restrictive places but for more restrictive places the 30/60 can still work. Still, SO could have made the angles 37.5/60 which in conjunction with the standard 15' wrench would have split the variance between 15' and 60' in half giving us the ultimate combination.
I wonder if SO will ever make complimentary 45/75 angle wrench sets which does balance with the 15' wrenches while the 30/60 balances with zero offset wrenches.
Let's see, a standard and a FD set in both sae and metric and I'd need 2 more drawers.....so $$$ X 4 = $$$$$$$$$$$$$$$ + $$$$$$$$$ .........Forget it, manufacturers will have to make more sides on the fasteners so we can re-grab in less degrees!