I see they've rustled up some more signed cassettes as well as unsigned blue vinyl on their store. The red is now 'sold out'.
I've come to accept the 'that'll do' latter day Nana vocals for what they are. Keren commented on how Richard X had them sing Love In Stereo over and over (though I recently saw Will Young saying something along the same lines so it isn't just them), and they are clearly happier with a more casual approach.
I do wonder if that is partly why we get so many solo vocals now, as I imagine timing things for the unison singing takes a bit more effort. Their voices so seem to be more different than they were years ago too.