I'm using it and like it.  I happend to also have a Shearwater Sport and Chesapeake 17 (not LT).   There are several different brands of basically the same thing available, so shop and choose.  Finding the full 15-18' lengths needed without having to put in a seam or overlap is the biggest thing.  Also, I think it is a good idea to limit to 2 or 3" width, as wider widths will make doing curves without wrinkles harder to accomplish. I wrapped the tape all the way up above waterline at bow and stern. Make sure to follow directions, get the stuff very warm with hair drier or heat gun and pull hard when bending around bow/stern curves, then maybe even hold in place for a little while to maintain the stretch as it cools down.  This is necessary to limit the wrinkles - I have very small wrinkles in the outer (thinner) 1/8 inch of the strip at the max bend radius, but nothing bothersome.  I cut a V-notch 1/3 of the distance to center in from each side of the tape to make the sharp bend at the stern of the Chesapeake and overlapped the outer edges (stern edge under keel edge for streamlining and to prevent catching when pulling over a log or whatever).  (Sharper anlge on the V than shown below, but you get the "picture.")

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Finally, with a belt and suspenders approach, I ran a bead of gel super glue at each end of the tape to make sure it stayed stuck. I'm pretty sure having the keel tape can't result in a 0.5% difference in overall hull drag - especially if it means there are a few less scratches on the bottom. The stuff is doing fine after a year, prevented some scratches while paddling, boarding and disembarking, and makes it so you don't mind doing things like gently setting the boat down in a gravel or paved parking lot during the load/unload process, too.

   Thanks. Sounds great. I was planning to use the original KeelEasy product 2" wide black. What width and colour did you use. I am curious.

   2 inch - black !

I have also used KeelEazy on a number of boats.  The Bubblehead's advise/thoughts are spot on.  As he suggests it takes a bit of work to get it to form on the more sharp three dimmensional bends like on the bow of my wife's Frej (first picture below).  Once I did get it to stick to her bow, I found that when the boat sat out in the hot FL sun it would start to release, so I used a dab of superglue on the ends and it has stayed put since.  On less complicted shapes like the stern of her boat, I find that it sticks well without superglue.  An advantage of not using superglue is that without, KeelEazy is easy to remove with a heat gun when it comes time for repaint/revarnish.

I agree that the added drag of KeelEazy is insignificant as long as the leading edge on the bow is above the waterline.  

I also use 2" black.  Besides the bow and stern, it makes a great (paddle) strike guard on the sides of the kayak.  The 4" also works well to protect the area where your feet rest in the cockpit.  Both are shown on my Mystery.