The stock shafts in the i20 and G20 are different. The i20 shaft (TFC707) is a pretty decent one, and the one in the G20 (TFC169)is somewhat weaker.
The PX is not a "real" PX, but one made for Ping, and although it is higher launch, it is supposed to give a flatter trajectory, hence good distance. I have a Cally Diablo Tour Black with a PX 6.0. This is another "made for" version, less solid than a "real" one, but a bit better than the Ping version.
The "real" PX Tour Issue shaft, as seen in a Titleist 910 is a very solid shaft and a lot of players have struggled to flight it properly. Great shaft if you are up to it, though.
