Actually, while it is true that there is not too much on the other satellites (except Galaxy 10R), AMC3 has some worthwhile stuff: various PBS channels, CreateTV, PatientChannel and TipTV.
But some of them, especially the PBS channels at "12179 V 30000" are hard to pull in. I had to use fine tuning on the motor positioning to get them, as the default position (which was set via USALS and normally works well) was a bit off for these signals. At least that is my experience.
Another drawback is that many of them are in Dolby audio, so if you don't have a home theatre system, you need to get a decoder and plug it into either the optical or the spdif output. I got around this by purchasing the Sonic Voom headphone system from eBay (appx. $20) and plugging a stereo mini plug into it's output, and from there into my speaker system.