Lorne, you mention putting a strip along the keel, look at the areas of greatest wear first then consider whether something along the entire length really puts it where it's needed. I find just a 4"-8" strip on the ends wear a lot. Under the entire hull there is just about as much wear as specifically the keel line. kevlar will be fuzzy when it's abraded. why not simply add a couple extra bias cut strips of glass at the ends with a couple strips of Dynel on that . A strip of 6oz kevlar tape will soak up a lot of epoxy and will require fairing in. A few skinny strips of glass and dynel will require less fairing in and less epoxy while putting the stuff where it's needed. As far as above and beyond normal abrasion resistance for the entire hull bottom I'd still be tempted to stick with another layer of 4oz. glass as the synthetic cloths soak up a lot of resin.