I use it as it's the stock launcher on KitKat. I've used several launchers (ADW+, Nova Prime, Apex, Aviate, SFLauncher, Action Launcher, and so on...) on my phones before, but on the Nexus with KitKat the stock launcher works really well for me, especially now that UK English has been enabled for the 'OK Google' feature.
Pros: Smooth, Intuitive, Google Now built in; basically it's been well designed.
Cons: Not customisable as such, though if you're rooted there are some Xposed modules that let you change grid size, the number/size of icons in the hotseat, removing the searchbar etc.
If you're running 4.4+ then it's worth trying. There are a few free variations on the play store which are fully customisable but they lack the full Google Now integration.