Three methods:
1. Pick one and try it. If you like it, stop. If not, try another. And so on.
2. Study reviews and tutorials from all and pick the best according to those sources.
3. Try all and keep the best.
At present ,there are five video-stitching software,panovideo , AVP ,videostitch ,PTGUI ,Hugin.and there are two 360 panorama video live software: Vahana VR(live) ,panolive.
Who can tell me how to select?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic