The Walther PDP Pro SD Full Size 5.1" is the suppressor-ready version of Walther's full-size PDP, with a threaded barrel cut 1/2 x 28, an optic cut, and three 18-round magazines in the box. It lists at $999. The buyer it fits already likes the PDP grip and wants a factory suppressor host without sending a slide and barrel out for work.

The Pro SD swaps the standard PDP's Performance Duty Trigger for Walther's Dynamic Performance Trigger. The standard Walther PDP Full Size costs $300 less, is 0.5 inch shorter with a 0.6 inch shorter barrel, weighs 3.0 oz less, and ships with two magazines. The HK VP9A1 X Tactical costs $150 more and holds three fewer rounds per magazine. The FN 509 Tactical is $10 cheaper, uses the same thread, and holds one round fewer.

Buy the PDP Pro SD if you want a threaded, optic-ready striker gun with Walther's Dynamic Performance Trigger and an extra magazine already paid for. Skip it if you will never mount a suppressor; the standard PDP Full Size gives you the same grip for less.