I don't think you need the extensions, personally. The half inch shorter may have the
clubs playing a little stiffer, unless they came from the factory that way.
The reason it's 10.50/club is to cover the costs of the extensions and new grips. If you were going to regrip the
clubs anyway, you might as well get
Ping to put the extensions in.
Grips are anywhere from 2.50 to 5.00, and extensions are ~ $2.50. SO it's a not bad relationship of 1:1 Parts:Labour.
You'll probably see a 5-7 yard distance loss without the extensions.