“need” is relative to your desires, wallet and level of patience.
LW has the tools to do character animation. Throw in ACS4 ($90) and you don’t even have to worry about most of the rigging process. There are some bone tools coming out from Irrational Tools that will make rigging much less of a hassle as well.
Where Messiah excels is primarily Speed. It FLIES. Lightwave gets very sluggish when you have complex or multiple simple IK chains. There are ways of making it speedier - but it is still no where near M:A’s speed.
Messiah has a lot of really nice tools but you can get work done without them. Just takes a little more patience.
Messiah, Lightwave and C4D all have demos available with tutorials. The Lightwave demo should downloadable soon…or so Newtke says.
Make sure to work with them all a bit. Look for online tutorials on rigging, animating, texturing, etc. and see what you think of the workflow. You won’t go wrong with Lightwave or C4D - they are both very capable and stable apps.