Kicking off the comments discussion, I'm using MythTV in my production set-up. I'm still playing around with LMCE, so it's running in a separate test environment. When I'm done testing, and I can sync up the various MythTV levels and do a database export from prod and import to LMCE, I'll flip over to LMCE as the prod environment. Don't have a lot of free cycles right now with work being busy, family life, and a Z/OS course on the side, so I'm not sure when the cut-over will happen.
My Master back-end is running MythTV 0.24.2, and has two PVR-1600 cards in it. The analog inputs are connected to the CATV line (we still have analog on CATV in Canada), and the two digital inputs are hooked to a home-made 4 bay bow-tie antenna, picking up the local ATSC channels.
I have a disk-less slave back-end/Front-end running MiniMyth, with two PVR-150's. One is hooked to CATV, the other is hooked to the Rogers STB. I have three other MiniMyth disk-less front-ends running.
I'm excited about the release of 0.25, as I see the services API as a stable means to accomplish remote control of Myth. 0.24 came out with 'events', which 0.25 is extending on, which could be great integration points into LMCE DCE events. 0.25 also has AirPlay/AirVideo support baked in, the new OSD message class (send CID events discreetly while watching media), plus a whole lot of other bells and whistles.
Have a good one!