I did not say that any scope was not useful. What we are discussing is the characteristics of a scope for all around use.
What do you mean for 'all round use'? - to take that literally there's no actually such thing.
For 'all round use' pretty well any 'proper' scope, either analogue or digital, would be perfectly suitable - but no matter what the specification there's going to be the odd occasion where it's not suitable.
But as I've said, higher spec scopes are only slightly more useful than far cheaper ones.