The advantage of the armlock is multifaceted but the main benefit is increased face control. We orientate our JMX/SIK grip parallel to the putter face for maximum contact points, ensuring a stable and square setup from address through impact.
If the L.A. GOLF SHAFT is an option for you the benefits in face-angle consistency are measurable. The shaft is extra-stiff but is also very responsive and retains a "buttery feel" on center strikes.
The Pro C-Series Armlock is the putter that Bryson used to win 5 times on the PGA Tour, 1 on the European Tour from 2017-2019. The head weighs 370 grams with the Armlock-Plumber's Neck.
The DW is basically the Pro aesthetic (classic anser style) from address with double the width. This allows for the advantages of a mallet (MOI) with the look of a blade.The head weighs 390 grams with a Armlock-Plumber's neck.
The Flo, while aesthetically unorthodox, is a definite performer with its high MOI. The Flo is weighs at just over 415g with the Armlock-Plumber's Neck.