I tried ae, shake and fusion... in the near future I will dive into nuke too.

And till now... so w/o any exp. in nuke... I prefer shake. Node based rules and although it has some things missing it got some nice things fusion doesnt have. e.g. color concetenation and infinite workspace... and it is my main work-tool.

AE is nice for Motion Graphics or better: in Shake it was horrible, but Fusion can cope with it pretty well...

But in the end, as always, it depends what you feel comfortable with.

greets