I use and like Geany on Linux. GTK apps on Windows have always been buggy for me though. Geany had a strange issue where it would sometimes maximize larger than the screen, so the only way to get control of the window again was WindowsKey+DownArrow.

I also have trouble finding nice themes for Geany.

Sublime and Notepad++ are much more polished, but I plan on giving Atom a legitimate trial now that there's an official build.