Qt5 vs GTK3
What kind of widget toolkit do you like more?
And why / what kind of features make it better?
My personal favorite
I personally like GTK much more because it looks very clean and modern. It integrates great into GNOME (obviously) and it's just simply beautiful. It may be a bit too simple for some people, but I'm alright with the simplicity.
I also do like Qt5 but it has a kind of Windows feel to it, and it's license is a bit odd, especially since KDE is now having some problems with the newest licensing changes etc. But it's so easy to create Qt Applications.