So I'll be picking up an M5 used sometime in the next two weeks, but looking for a wide angle solution too. I have been really looking at the Rokinon/Samyang 12 f2, but I'm wavering between it and the EF-M 11-22. I know they each have their pros and cons and they are about the same price. I love my primes and the 12 f2 definitely appeals to me there. Seems like a neat lens, but I don't have a lot of experience with manual focus and the weird interaction between the lens and camera body is a bit of a turn off to me. The EF-M seems like it will just work, so maybe I should just do that. I had the 10-18 before and it was pretty good, but felt super cheap and it was a bit large IMO to go with the M system.
I don't shoot astro, but I would be using it mostly indoors or on vacation. Occasionally for rolling shots of cars (IS could come in handy there). What do you guys think?