Harbeth Owners which model?

I am looking to buy either a M30.1, SHL5, or M40.1. I owned a SHL5 in the past for about 3 years and totally enjoyed it and have regretted ever selling them. Since I sold the SHL5's a few years ago Harbeth has come out with the M30.1 and I wanted any feedback from anyone who has compared the 5's vs. 30.1? Anyone sell their 5's for the 30.1 and why? Lastly I am also interested in the 40.1's my room is 18 x 14 is that big enough to handle the 40.1?