I've worked with several. One poster says to stay away from BSI, and I've heard the same thing from former co-workers who've used it, though I have no experience with it myself.
I always liked Audio Vault for music stations. I wouldn't recommend it for talk stations, though. It always seemed like you could never get it to work for satellite programming. You just tricked it into working! Also, while I thought Audio Vault was easy to use for music programming, it wasn't always the most reliable system. If I ran unattended for much time at all, I probably wouldn't use Audio Vault.
Scott Studios was probably the best, but I've heard nothing but bad things about it since Google bought it from dMarc. I don't know if the new owners have made it any better. Also, while I loved Scott and DCS, I absolutely hated Maestro, which was an updated Windows version of DCS essentially made by Scott Studios. Don't know if Maestro's still supported or not since it was a dMarc system that was bought by Google. Last I heard, Google was going to fold the two of them together.
I've also worked with Wire Ready and didn't find it to be too bad. I always thought it was almost Scott Studios Lite!