They really were as good as they sounded, with all the feeling of a traditional string quartet, but playing folk tunes.
Rather than facing the audience, they sat in a circle of four facing inwards and kept rotating between sets so you got to see all of them. This was apparently so they could communicate to each other during the performance.
There are some samples on Myspace - well worth a listen.
Having bought a copy of the CD on the day, I was impressed when I got home to find it was numbered YAN001, very fitting for a band called Methera.
*goes off to count sheep*