I use DADGAD probably 75% of the time. The only disadvantage I personally find is finding my way round some minor chords, I still tend to play some songs in minor keys in Standard tuning or with a dropped D. Otherwise it's the greatest tuning ever and lots of fun and very versatile for all sorts of different styles.

Dick Gaughan uses this tuning fairly exclusively I think, if you want to know why it's a good tuning it have a listen to some of his stuff.

Happy exploring...