I like the 99 series. Good design.
I ordered a SW99 after participating in an extended T&E using a pair of SW99's chambered in .40 S&W and 9mm, and attending my first SW99/P99 armorer class. I later carried an issued SW99 chambered in .40 S&W for a few years, and then ordered a SW99c chambered in 9mm. Like the Glock, I tend to prefer the 99 series when chambered in 9mm, myself.
There are some features in the 99 series which I think are genuine refinements when it comes to the concept of a polymer-framed pistol.
I've written a few posts detailing my thoughts about the 99 series and won't burden folks with recreating them here. Suffice to say I feel it's a robust, reliable service-type pistol which deserves more attention than it received in this country. Walther doesn't really promote the 99 series here, and I'm told it's presently devoting significant effort to promoting it in the rest of the world for LE & military sales.
FWIW, I also tend to prefer the 99 series in the traditional double action format, which Walther now calls their Anti-Stress.
I've put many more rounds downrange in training & practice with my SW99c than I have my 3913, and about an equal number of rounds compared to my G26 (more than 9K), and I find the inherent accuracy of the SW99c to be just a little bit better ... for me ... than either my 3913 or my G26.
Nice pistol.