i've used many of the other DVR/PVR applications (MythTV, SageTV, Nero, etc) but none have worked as smoothly as Media Center, Windows 7 MCE really brings its A game.
i have a remote and IR blaster and mainly use mine to record just network tv; i can also easily access any of the recorded tv shows over my homegroup on any of my other Windows 7 laptops/netbooks and even my PS3.
MP4 movies look and work well inside of MCE too (atleast on Win7, vista had a few issues w/MP4/h264 codecs since it didn't support it natively). I run MCE on my HP laptop and use a MCE remote i got with my tuner card. Netflix plugin is really well done too.