I would say whatever length allows you to hold the putter in the middle of the grip when you take YOUR putting stance. There are so many individual ways to get over the ball for a putting stance (watch Michelle Wie and Bernhard Langer for example). Each person has their preferred stance so it all comes down to how you position yourself to hold your putter. Unfortunately there is no one magic position that will work for everyone :(

Hi Mark,
Great timing!

Scotty Cameron just posted the following on Instagram this morning:
"Putters are not pendulums.
Putters do not swing vertically back and through along the target line. Because of lie angle, the proper putting stroke moves along an arcing path: slightly inside of the target line, back to square, then to the inside again after impact. The proper length putter correctly sets eye position just inside the target line, and the correct amount of toe flow allows the putter to flow squarely to the proper arcing path throughout the stroke.The best players in the world keep the face square to the arcing path and the butt of the putter pointed at the midsection throughout the stroke. Selecting the right putter will help you do the same."

We hope this helps!

Cheers,
Mitch D

Good luck Mark. You are going to love the notchback - I have the original black version and it is hands down my favorite club in the back - plus I find that with the notchback it is much easier to line up.