How bad Jackson is depends highly on which problems are attempted and in which context. The content is fine and perfectly understandable. We used it during my third year of undergrad. Homework mostly consisted of the easy-to-medium problems, and self-study could focus on the medium-hard.

Between that and the highly-abstract statistical physics course (it started with an introduction to differential forms), I learned more in my third year of college than in any other.

That said, I now work in IT.