In reply to alan moore:
Malin Beg is prone to SW motion and catches all the lumps coming in, it the sea is calm most of the routes are non tidal. Cruit Island is a good alternative as it has crags facing all directions and climbing is possible in all sea states. (it's an hours drive up the coast from Malin Beg)
Mucros Head is excellent if you are operating at E1/E4, if you are a sub E leader then one day's climbing and you'll have done all the routes. It is also prone to SW motion.
Di/Triversion is the quickest drying bit of rock in the Donegal mountains, needs two full days of dry weather. Tarquin's Groove is the crags drainage line and needs about a week of dry weather.
http://www.pete-smith.co.uk/dynamic/guidebook/index.php is the current guide site.
Hope this helps.
Iain