The rear wiper was corroding, looked scruffy and would skip a section at the top centre of the window.

Of course I could sand it back, paint it, lube up the joint.
Or, I could spend a whole £17 on a replacement arm (with blade) from Amazon. Which I did.
Weirdly a lot of people recommend the e70 arm which supposedly works better and looks more modern, however the curve at the mount end goes the opposite way, it’s designed to sit on the right when not in use. No way I could fit one, would drive me insane every time I looked at the rear end