I have seen no performance change between plain, dipped and wrapped arrows. In a truly technical sense, yes a wrap will reduce your FOC a little bit, however at most, you are probably looking at about a 1.5% change. In my experience, unless you are on the hairy edge to begin with, the wraps have no negative effect.

From the practical side, they make refletching significantly easier. No more scraping glue off the shafts and potentially gouging the carbon.

As for the comment about finding your arrow after a pass through, that is spot on. Even with a bright fletch, I normally spot the wrap before the fletch.