I got my copy of that CD recently. I like a lot that style of singing. Mostly a single unaccompanied voice and a very good collection of songs. How you get together such a collection of good voices in a small area is a secret of Ireland. If that's really "typical of a night at one of their sessions" I can only envy you.
Go on and buy that CD unless you hate listening to a capella singing for more than one track.

Wolfgang