I've used Inkscape a bit, though it was a couple years ago. It definitely isn't as good as Illustrator and if you're thinking of doing a lot with vector there is really no comparison. BUT for the price (free it does a decent job. If you're doing simpler stuff it isn't bad. I don't blame you for wanting to avoid CC--I'm super glad I got CS6 when I could--but if you end up doing a lot with vector, then... well, Illustrator has my vote.