Coming from Paint.NET, I first tried Photoshop and I felt its controls to be non-intuitive, so I reverted to Paint.NET.
Later, I started using GIMP and coming from someone with no experience in either of them, GIMP and Photoshop are equally non-intuitive, so whenever someone complaining about GIMP, feels like they are coming from Photoshop, I just discount their rating.
Inkscape is a vector graphics editor, which is different from GIMP.