Having been to Pas, visited Soldeu, and stayed in Arinsal, all I can say is Andorra rocks!!
Pas go to the Underground and the Mexi Shack night!!
Soldeu - only had lunch but thought skiing was ok round there.
Arinsal - Skiing not amazingly challenging but ok, not much snow when I was there. Princessa Park - v nice!!

I played a couple of acoustic numbers in there! Free cheese toastie in El Cau (The Cow) when you buy a drink at the end of every days skiing!! Plenty of night life for such a small place
Free bus to Arcalis (great skiing area, v quiet!)
Oh and has anybody mentioned that the resort is TAX AND DUTY FREE!! Cheap as Chips!!