Hi Siggi,
Just tried both the R15 and my Ping lvl 81 3W again on Best of Par 5 B9. Using that WGT G13 S vapor ball, with no enhanced distance, I found them to be virtually identical. Played all holes in mulligan format, with no driver, so shots were the same, same aiming point, etc, as much as possible.
I had 8 dinged shots with the Ping compared to 5 for the R15 due to the meter speeds 3.5 vs 3.0. I had one shot with the R15 on St Andrews where I caught a lucky bounce on top of the hill on the fairway and it ran down the back side further. A total of 265 yds. But i could only do it once, as I pulled it left. I also had one shot where I couldn't keep the R15 out of a bunker, due to hitting it a little late every time.
Using the raw date, I found the following averages:
Pin G25 lvl 81 4133 yds combined with 17 shots between tee and fairway shots, giving an average of 243.12. R15 4363 yds combined with 18 shots between tee and fairway shots (with one more fairway shot) for an average of 242.39.
Since most of the shots were within 1 yard between them, I find that if you throw out the fluke drive of 265 yds and the shot in the bunker of 199, and replace them with the Ping shots of 250 and 234 yds respectively on those holes, you get a total distance of 4382 yds for 18 shots, or 243.44 yds per shot average. Or 1.05 yards per shot.
If you keep the fluke drive and throw out the bunker shot, and replace it with the distance from the Ping shot, you still only go to 244.33 yds average, or +1.21 yds per hole.
My Ping G23 was 745 credits. The R15 is 1395 credits. I didn;t have any issues with the difference in forgiveness of 3.5 for the R15 vs. 3.0 for my Ping. And I'm trying to change over to all clubs with a 3.5 meter speed. So for me right now, my Ping works just fine.
hope this helps
Phred952