The Center Cut mod. 15 ion is designed for players looking for a heavier putter that encourages a pendulum stroke. GigaGolf says that the ion version includes a milled alloy insert encased in a vibration dampening polymer that minimizes the ball tendency to hop on impact, and delivers exception feel.
The extended mallet design has a “saturn stabilizaiton bar” (rings of Saturn—get it?) to increase the moment of inertia and thus reduce twisting. The three ball alignment system is one favored by many players today.
The GolfBlogger is very much in favor of heavier putters. My two favorites these days are much heavier than normal and I am convinced that they take any wristiness out and promote a smoother stroke.