I just bought a couple sleeves of the GI-SD balls to see what I've been missing... I've been using the GI-D's, it seems, forever.
Having made it through a sleeve of them, I've DEFINITELY found that the SPIN characteristics are different... even on putts. Either I'm imagining things, or the -SD balls are truely influenced more by the slope of the greens. Any thoughts about this?
The distance changes are as reported earlier in the thread... and I've found that adjustments indeed are necessary, especially with full/max swings and "spin-dot" placement variations.
Cost/benefit ratio is still being assessed, but I've got one question about ball changes that I've often wondered about:
Although it would seem to be a massive undertaking by WGT's programmers, if the clubs are rated using the UL ball, why can't a club's "max" yardage (on the meter) be changed to better reflect it's actual potential distance, when using a different ball? Asking for too much?