I never heard them, but I used to listen to Horslips a lot - in fact, I have most of their records (how did that happen?). I actually liked the ones that veered away from the Irish stuff the best, after they broke in the U.S. (and were marketed as a Jethro Tull-like band because of the flute!). Alien was probably the best - I associate it with very painful memories of my past.
I have not a drop of Irish blood in me. However, since my mother is from Brittany, I do have that Celtic thing going.
Bertrand.