I recently picked up a Centerfire / Goliath mallet Void with a KBS Tour GPS 120 graphite shaft. This Zero Torque craze got me looking around for a putter that didn't cost more than a new driver or on par with most of the six club Direct to Consumer iron set.
I have only played four rounds with it and am still getting use to a center shafted putter, but early results are that thing has amazing promise.
Through my reading of early reviews the Void insert touted its ability to be very consistent with distance on pure hits and on off center strokes, therefore helping with lag putting. And I have to say that my lag putting has improved greatly. I don't make all my 20 - 25 foot putts (of course), but when I miss I probably haven't been more than 2 feet from the hole and have had early tap in second putts. FYI, only two three putts in the last four rounds.
Insert assistance for distance control and zero torque are two powerful technologies. Now its up to me to get use to a back and through stroke after years of putting with a toe down Newport style blade.