I have BestSkinsEver on all of my MacBooks. They are really good and fit well but they are a wet install. If you have done one before its no big deal but if not it can be daunting the first time. I'm pretty OCD so fitting one takes me a solid hour to get perfect (lifting, correcting, removing bubbles, etc.) I always use their matte finish, as you will only see the skin on very close inspection. I have done maybe 5 or 6 of them over the years and they have never lifted or yellowed during the time I owned them. They improve the grip a lot and offer some scratch protection on the bottom...but not the edges of course. They are a great option if you want to keep the original look.
The skins such as DBrand and SlickWraps are great as well...I have used both in various colors / textures. As macfrik said, DBrand does seem to have a better fit in my experience than I have seen from Slickwraps but they more expensive. With the color skins, I tend to get sick of the look after few months and end up going back to BSE...but thats just me. If you like the look they protect well and add a distinctive look.