I've recently purchased the and was curious to find out the difference between the G15 line versus the new K15 line. Since I bought my Pings from , I always have the option of trading it at 10% loss. That being said, what I've found out will online golf clubsmost likely make me keep my G15's and pass on the Ping K15 Driver's. For the driver, here are some of the differences:
1) G15 offers in 9,10.5, 12, 13.5 loft options while K15 comes in 9.5, 10.5, 12.
2) Even though both set up with neutral offset, K15 appears to be more draw biased with the weights in the heel to promote the closing of the clubface.
3) Even though both designed with the stretched (elongated) club head, G15 offers more of a "classic" look while the K15 appears more elongated.
4) Off the shelf, G15 offers the Aldila Serrano shaft which plays stiffer and lower trajectory than the Ping TFC 149D shaft. The K15 only comes in the TFC shaft off the shelf.
5) G15 is a low spin driver while the K15 is a mid/low spin driver.

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