Modolo stems: Equipe, Flash, Q-even, Professional
 

I searched all over the web, but I can't find the difference between the Equipe, Flash, Q-even and Professional stems. I do think the Equipe is lighter than the Q-even. Correct?

Does the Flash fits below all?

I've heard of a recall for the Professional stems. Does the same cracking issue applies to other models too?

Would like to know as I am considering them for my Vitus ***9/Zap build.