i've been happily using MC for all my media uses, including as a server for my Sony Blu Ray player, for a number of years now. I have, however, encountered a few limitations, but i've generally worked around them. I have found that the server works best when set to not convert format, however, by doing this the Sony is only able to pick up AVI or DIVX video files. As most of my library is AVI or DIVX this is ok. Recently more sites have been moving over to MP4 or MKV formats (and the quality of MKV is pretty stunning so why not!) and in order to play these files I need to do one of two things - either stick them on a USB drive and plug in directly into the Sony (which will play pretty much anything you throw at it this way) or set MC18 to convert to MPEG2/DVD PAL stream. Converting does work however, the picture quality isn't always that good - things can get a little blurry in the background, and it reformats everything to 16.9 rather than keeping the original aspect ratio, which is always preferable. Tried using 'convert when necessary' as assumed this would be a best of both worlds option - retain AVI and DIVX as normal, convert MP4 and MKV, but this doesn't work - it converts AVI and DIVX, even though it doesn't need to and still doesn't recognise MP4. So it's either convert everything or nothing. So basically I'm left with a lot of running about changing the options - convert, don't convert, use USB drive. Generally covers all grounds but isn't perfect.
Just out of interest I recently tried out Serviio and discovered that it will stream all media including MP4 and MKV to the Sony without conversion. It did of course have it's own set of problems so I'm still using MC18, however I'm pretty curious to know how Serviio can stream these files to the Sony without conversion but MC18 can't?