You'll probably find that an alloy base will fatigue in that area somewhat quicker than the Victa steel chassis.
Not in my experience Bonnar Bloke. It won't fatigue if it doesn't flex in the first place. The thicker alloy metal is very rigid and doesn't seem to pose a problem with these handle mounts.
Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!