Nah, with distros these days, it's no more than a day to get a basic system up, plus another day of noodling to fine tune things... well, assuming
I disagree. MythTV takes about a day to get to the point of doing "something useful". But I am a Tivo fan and I wanted MythTV to be as much like Tivo as possible. That part, getting MythTV to be like TiVo, took me a about a month.
I used a TiVo for seven years until last week. I got about 99.9% uptime with TiVo over that time. I used MythTV from a distro for the past two and a half years. I got about 95% uptime and there are many little hassles compared to Tivo. I also shut down the MythTV last week.
Now I use a new Windows 7 computer with Windows Media Center. I spent about two months comparing several PC based DVR options: Liquid TV, SageTV, BeyondTV, GBPVR, and Windows Media Center. All were a hassle, each about 100 times harder to set up than Tivo. And each only about 3 times easier than MythTV. For a time I was afraid none would work out. But eventually only Media Center was left standing and now it is working rather well.
Media Center is not quite as nice as Tivo, but it has most of the features I wanted. Plus it has one great feature I always wished Tivo would have: 3X fast playback with audio. A wonderful feature.