I think the folks using them for heavy duty applications are sort of missing the point of them. They seem (to me) to be intended for moderate duty applications, particularly cold weather (more comfortable to hold), where metal tools might spark or scratch paint, or where you would want a lighter weight tool for some reason. I don't look at these and think, "oh, I can use that to remove an engine and break free rusted fasteners", just like I wouldn't use my 1/2" breaker to take off my battery cables.
I am curious, do these get brittle in freezing conditions?