I have a couple of Rocket Tour Headcovers (Navy/Yellow) for my fairway woods. Couple of issues I have wtih them is that two holes have been developed on one, not sure how. The other issue being that they tend to slip off my fairway woods. I'm always trying to tuck the end into the bag so it 'nips' against the inside of the bag to prevent loosing one, but still I'm always checking to make sure they are there.
I have three other animal headcovers as well. The Sergio Black Bull (just because I like the bull), a Warthog, and Marvin the Martian. Marvin and the Bull are my favs...but Marvin is well worn, sewn back together, and fits pretty loose. So I'm looking for something new as well.
Daphne's seems to have one of the best selections of animal headcovers, including hybrid covers too. I'm still undecided for myself.