Hi David,
I would say ProAnimator and Invigorator Pro are at the tops of their respective food chains. They have common roots, but in some ways, these are very different animals.
If I had to choose justs one, I would choose ProAnimator. Here’s why:
Motion control. ProAnimator’s non-keyframe motion control system is the best in the business for creating very complex motion simply. Invigorator Pro uses AE keyframes and has significant limits on the number of object sets that can move independently of the others.
Stand-alone and plug-in. ProAnimator can be used either as a stand-alone or as a plug-in for After Effects. That choice gives you a lot of workflow flexibility. Invigorator requires AE as a host.
Bonus features. You can leverage ProAnimator’s amazing motion controls to control other objects in your AE timeline. Simply save your ProAnimator project and import the motion data into the AE timeline. You’ll get placeholder solids representing each element. Those solids can be reassigned to other solids or precomps.
Having said that, ProAnimator and Invigorator share modeling and texturing abilities and can do 3D text on the fly. Their evolution from common roots gives both products very strong foundations for the future.
Long story short. ProAnimator is a great choice. Hope this helps.
Jon