I've a tip about this in shopping as well. . .we purchased a few small gifts here and were even tempted by some of the wool items.
But, our bus driver (Dan - wonderfully charming man!) put it this way, "This week the sweater fits you; next week the sweater fits you and your friend!"
Unique Suggestions: Be careful with the sweaters. . .
Fun Alternatives: At the base of Dun Aengus in a buidling near the entrance, a local woman knits her own items. These are authentic Aran Island products and should stand the test of time.
There are several sweater shops all over the Island (and pretty much the rest of Ireland). The sweater stores have displays and videos about how the people of the Islands have been keeping warm in these sweaters and have descriptions of each family having their own stitch patterns. I was almost sold on getting one, until I read that the Aran Island sweaters aren't exactly that old of a tradition. It started about 100 years ago and the stitch patterns is pretty much a recent invention. Their manufacturing only took off in about the 1950's and then pretty much for tourists.
Unique Suggestions: Don't completely trust what I've written, because there are many other people who say that these sweaters have been worn by fisherman of the Islands for (upto) thousands of years ago. So the claims in the sweater shops may still be genuine. But, since it costs 80 to 120 euro each, I would make sure that I really like it and I would still buy it even if it was a recent invention.