Just picked up a refurb 55-200 on sale ($250) at the Canon Online Store. Really bounced back and forth between the 18-150 and this lens and ultimately came down on the 55-200 for the extra reach even if IQ is a touch better with the 18-150. My wife and I both have M5s. I primarily use the 22mm and the EF 40mm pancake with adapter when shooting with my M5 (I mostly shoot with a 5D3). She uses M5 all the time with an 18-55. She'll be the one using the 55-200 most of the time. Hope I made the right decision.
Ed
Ed