I have owned both the Ping K15 Driver and G15 Driver. I thought I would add my two cents: if you are a slicer the K-15 is the best thing since sliced bread. The heal weight really does enable you to turn your hands over effortlessly and hit the ball straight or even with a draw. The big advantage here is that you can swing harder and still turn your hands over, and thereby get distance you have never had before. It's cool to be able to unleash your drive and not slice it.
The advantage to the Ping G15 Driver is that I think it has a little sweeter sweet spot. When you hit that right it feels better than the cheap ping k15 driver in my opinion. But you may have to slow down your swing a bit to get it over. It definitely feels heavier in your hands, and harder to turn over. But it is also much easier to hit a power fade with the G15. So each is a great driver with different design goals. Take your pick. Both will hit it a long way.
It took me one trip to the range to work out the kinks of this discount golf equipment. I am a lefty and have or should I say had a severe banana fade to the left. After researching many drivers I decided to pull the trigger on the K15 - 9.5* loft, stiff shaft. I am getting an extra 10-15 yards to put me between 265 - 280 consistently straight down the fairway. My mis-hits are still going around 250-260 with only a slight fade at the end. I couldn't be happier and I can honestly say this is without a doubt the best driver I ever hit.
Both my G15 Draw and K15 sit mostly square, so compared to your non-Draw G15, a K15 should sit similarly. Ping generally does their "draw" bias through weighting not by closing the head, as in the K15 and G15(http://www.dealgolfclubs.com/Discount-Ping-G15-Driver-87.html) Draw. I appreciate the extra help getting the head square, and the K15 just has a knack of hitting the ball straight.
Cheap ping g15 driver is often a very low spin car owner whilst the K15 can be a mid/low rotate new driver. Seems like this K15 Driver is a real option to the actual Extremely Game development Rapture collection. That said, the design and shade looks like it's nearer to your G15 than the previous Rapture.