I would not buy this kayak without trying it first. Don't expect to be good after the first try unless you are an experienced paddler. Some people say it takes a month to be comfortable and fast in a fast narrow surf ski if you have little experience. Some people learn faster than others but most people take time. And to race against experienced paddlers it takes a lot of experience.
When learning to use the kayak I would not have padding in the seat as it will make the kayak much more tippy. Gradually add padding you gain more experience. Also when out in the open water make sure you do not separate from your kayak, as it is easier to stray away from you when you flip than some closed cockpit kayaks. I have a friend who was rescued by the Coast Guard when he lost his surf ski in the Atlantic.
I rated the Blade an 8 because it is a specialized boat, that requires much more experience than most kayaks. But it is obviously a 10 for those with more experience and who use it for it's specialized applications such as working out and racing.