For the price. The Walther trigger left a lot to be desired and only holds 15 rounds.
Canik is $435 and Walther is $735. For that additional $300 you get less capacity and adjustable sights.
Most ppq's I've seen are around $500 unless you are talking about the 5" guns.
You also get Walther's customer service, which is very good. You aren't dealing with some importer and a company with no US presence.
Walther makes 17 round mags, and some of the larger canik mags will lock in and feed in a ppq, though they may not lock open