[Haskell-cafe] Best Actor system?

Having been introduced to actors by looking at Erlang, I discovered Akka. It seems that the performance is pretty impressive and I like the model. There seem to be several basic Actor libraries in Hackage, but they don't seem to be very actively developed. I'm more interested in the model for programming within a single runtime than I am for distributed systems, but message and dispatch performance definitely is important. Can anyone share experiences with the different packages? Is any one of them stand-out? Thanks James