I do like the look of the speed kit, and it really compliments your aircraft nicely. I didn't get quite 8 Kt on mine, but it bumped it up a bit, actually it has made the 185 slow down a lot slower, kind of a bit more slippery. The only thing I don't like about the kit is jacking the airplane with it, kind of a pain. If you have found a clever way, I'd love to hear about it. I am putting a lifting rig in my hanger to pick from the float hoist points and use my spreader rig to lift the entire plane, rather than jack it.
BTW, if anyone needs the plans to make a seaplane spreader for 180/185 I'd be happy to share my plans.