Hk - I 've pretty much been on the Bren train since the beginings. Never heard of of weak frames. Cracked slides yes, especially on the Special Forces models. Extractors, slide stop breakages, Mag probs, and such, but the frame is a new one on me.
Now maybe the Voit designers thought they could head some problems off at the pass by beefing up the frame maybe ? I do not know. But I guess anything is possible, and you can't hear of everything.
And there is a lot of us praying for a resurrection of the Bren. But a lot of experts say it is like the Automag - too cost prohibitive.
Reinz