I got my copy of Bela D Media's Celtic Wind last week. I haven't had as much time to work with it as I would like, but so far I am very impressed! I should mention that I don't have much of a background in celtic music or instruments. That said, these instruments are very easy and very fun to play! The way the instruments are programed makes it a joy to play. It's been a lot of fun to go through the different instruments and be able to use them musically very quickly. I'm new to scoring, but I think this library is going to be useful for a lot of different situations.
Here is my attempt to use the library: www.fullmotionaudio.com/music/CelticDance.mp3
This uses the Uillean Pipe, Low Whistle F, and War Horn. The percussion is the Frame Drum from RA and some claps from Stylus RMX.
Disclaimer: I won this library as a prize for the GCEmpire Chrismas Music contest. I did not pay for it.