Probably not. I am rewatching them, but I got distracted by real life and other things after a couple of lectures, but if you're farther in I would think it's not necessary. They're always there if you need them while you work through the psets, so I wouldn't take the time if you didn't think you needed them. Good luck!
They cover the same material but may be in slightly different order. I'd suggest reading the given notes for each lecture to make sure you still remember what was taught in that lecture. The notes are found underneath the video on the edX courseware page.