I had a C/Ku band satellite receiver for a few years and it worked well. I couldn't take it with me when I moved, so I gave it away. But I enjoyed it, so I'll probably have one again one day. The NASA channel was really neat when the space shuttle was in orbit. Most or all of the free channels are the first generation broadcast, so the picture quality is very good. These are the same signals that the cable companies and digital satellite companies receive and then re-broadcast over their system, making their signals second generation.
There are a few down sides. First, there are only a few free channels on each satellite, so channel surfing isn't really easy. The satellite receiver has to physically aim the dish at different satellites. So, if you're watching a channel on one satellite and you want to watch a channel that is on a different satellite, it can take ~30 seconds sometimes to change the channel, depending on the satellite location. Second, there are many different video signal formats now, so one receiver won't get them all. In order to receive all of the different formats (NTSC, DVB, Digicipher, etc..) you'll need a few different receivers and that gets a little expensive. Finally, channels moved around a lot and often changed format, so I had to keep looking for an updated channel list. I think a lot of this was due to channels switching to a digital format. Maybe things are more stable now.