Very nice choice! I see I'm late to the party to add encouragement, but you've already gotten your new Walther.
At any rate, I've had my Walther PPQ M1 for about 4.5 years now. I picked it up used, right when I started a stint working at a gunshop full-time. I personally find the Walther far superior to any Glock I've ever owned, so much so I sold or traded off all of my Glocks and accessories. In my hands, the Walther shoots as easily as a good 1911 or medium-frame S&W revolver, which is my standard of "Yeah, I can hit that from here" with a handgun.
I don't have a large amount of rounds through my Walther, maybe in the 2500-3000 round range. In that time it has never failed to feed, fire or extract. I did find myself accidentally dropping the magazine a couple of times early on while learning how to grip it for best shooting. It turns out even with my small-medium size hands, I shoot it best with the LARGE backstrap installed. This also solved the magazine-drop issue by giving me enough real estate to hang on to. (Side note: I see several of the other posters also have the LARGE insert installed on their pistols.) Recoil can feel a little snappy with hot hardball or defensive ammo, especially if I've been shooting lots of .45 ACP target loads in my 1911. But the PPQ is very accurate and easy to get good hits with; a 4" steel plate or the head-box of an IDPA silhouette is almost a give-me shot from 25-yards.
Even though the aftermarket isn't especially deep for the Walther, I personally don't find it needs much other than a decent set of sights, a good holster and spare magazines. My pistol wears a set of Trijicon HDs with a green dot on the front sight, and I haven't wanted to change anything else out. Just add ammo, use up and repeat as often as possible.