MPM - I'd have to dig up some pics of the installed SX Smart Tabs, but I installed them per the instructions and put them pretty far outboard on the hull so I could clear the bunks on my trailer and match them between strakes in the hull. When installed properly, they greatly improved my holeshot (remember I had the anemic 3.0L) and allowed for good cruising in the middle RPMs. They greatly reduced porpoising at all RPMs. They won't negatively impact top end speed at all when properly installed, they'll just get outta they way as you build speed, and full compress the actuator. They allowed me to run a small diameter (13 7/8") 23P 3-blade wheel while still keeping my RPMs clean on the little Mercruiser. It was a 50mph boat with that setup.
Since I only had the 3.0L and boated with light loads, I went with the 60lb actuators, not sure if you'd want 80lb actuators or not. If you call the place you actually get to speak with the owner and he can help you on install/application questions.
Good Luck and nice setup, that''s a very clean Sprint and it looks like it runs great.