Hi seamus, lot's of choices aren't there! It must be confusing, but all the advice here I agree with.

The USAK poly vis are great, I have several, they are great for work and play and are very tough.

Pure Scottish wool is wonderful when only the best will do. I wear mine for going out, special occassions or just when it's cold. I wouldn't wear it the beach.

So I guess it comes down to lifestyle and what your friend wants.
Whatever he chooses, warn him that they are addictive and he won't want to take it off!