OpenSuSE - YaST is as good as is made out to be. I like how many fundamental parts of linux are managed via one tool. Other distros I'd used before were heterogenous mix of tools that felt cobbled together and inconsistent, while YaST feels well designed, integrated and consistent.
Tumbleweed surprised me with how it receives constant, up-to-the-minute updates yet somehow doesn't ever seem to break.
It also surprised me with how much I like KDE. I had used it way back in the day when it was a bit complicated looking and ugly. These days Plasma makes the whole experience nice.