Am I missing something or are these the basic 3 players on the market? The good thing about all of them is that you can try before you buy. On some you can even take the time to learn it very well before putting down the bucks. There is also great price differences between them and feature differences.
You have MotionBuilder which has a time unlimited FREE Learning Edition.
You have Life Forms which has a 20 day demo version.
http://www.credo-interactive.com/trial/download_info.html
And you have Endorphin which also has a time unlimited FREE Learning Edition.
Although I prefer Motion Builder, Messiah (for me) runs a close second. It’s VERY powerful software and although I like Poser, it’s leaps and bounds above it - you really can’t compare the two. (IMHO of course.)