Recently I've decided to buy a new DSLR body (Canon 200D), and now I have to decide what lens to pair this with. forFor €18 on top of the body-only price I can get a Canon 18-55mm III lens, and for €94 I can get a Canon 18-55 IS STM lens.
I've compared the two, and even though the IS STM has a new optical design, it doesn't seem to score any higher (even a little bit lower) in dxomarkDxOMark (the IS II should be optically the same as the III, so I used the IS II as a comparison). The online reviews I've read and watched also don't point out any big differences. So as far as I know, the only real advantages are the image stabilisation and the better focus motor.
I mainly use my DSLR for photography, but I want to experiment with video as well when I receive the 200D. As far as I know, the IS and better focus motor are only really useful when used in video, so I was wondering if the extra €74 is worth the upgrade from the III to the IS STM, even if there's a chance I will only use it a few times for video. And are there any advantages of the IS and better focus motor in photography besides the more stable handheld photography?