The B was one of the worst. I have used taper core B and E strings with great success, but I'm sure disappointed in the exposed cores. The B and E strings were the deadest. They sounded like the strings were muted.My experience actually indicates an exposed-core B retains clarity longer than a non-tapered counterpart.
I've had situations where I was able to keep the same B (exposed core) when the other four were ready to be replaced.