I got a 44M-4 about a month ago along with a fotodiox adapter for my 5d mkii. It does have mirror hang so I put a very thing rubber band in between the adapter and the lens. The lens now doesn't focus to infinity but it does allow for a little bit closer focusing distance and stopped all the way down you can get everything in focus. Love the lens so far but haven't gotten to use it to much yet, but I picked mine up for $10 with a body at a thrift shop, friend ended up wanting the body and gave me more then what I payed for the whole thing, so far I have made a profit on this lens without even selling a print! Below are some fun shots with the cats eye bokeh.
Beautiful lens flare
So sharp you can see my reflection in her eye!
Even more bokeh