The Aurora Boat Scrub is a great product, but it's really just SoftScrub. I get it at a dollar store.
I remember using the Sure Step years ago and it worked, but was a pain to apply. We used it just a few weeks ago - 2 coats. It seems to work well so far (but it's inside).
I have also used Woody Wax, which if I remember correctly was much, much easier to apply but didn't last quite as long.
As to the Starbrite product, a friend of mine used to use it on his navy hulled boat, and found that the run off from rinsing marked his hull badly. That's something to consider. I think it may depend on what your hull is waxed with though.
My recommendation would be Woody Wax. It's a little pricey to purchase (~$30 for a can), but one bottle will last a few seasons.