It had a pair of them on my prior boat, a 19.5 ft fibreglass cuddy. They worked very well. Prior to installation, even the deep hull design on my cuddy took a pounding in a few areas that I frequent due to the areas having a combined effect with winds/current and tides. The ride was night and day after installation. I found the bow wondering that I had before with my I/O engine was greatly reduced. Much quicker time to plane and it kept the nose down to cut through chop. It also acted like a suspension in the transom so when you do bounce over waves the landing is not as hard as they have a cushioning effect. I also noticed that when I turned the boat the lean angle side to side wasn't as steep. Made the ride much much better and for the price point it was the best add-on that anyone can get for the small price.
Downsides:
1) If you happen to have any hydrofoils on your outboard or outdrive they must be taken off. The smart tabs counter-act the effects of the hydrofoils and does not perform well when both are on the boat.
2) If found it difficult to properly trim my boat in calm waters to maximize speed and fuel burn. Because the nose was push down by the lifting action of the smart tabs, I had a very limited trim angle on the outdrive and could not get the optimal trim angle to get me max speed and fuel efficiency due to the increase drag on a large portion of the hull being in the water. However, I didn't mind as the benefits of improved ride and handling greatly outweight the minor difference in not getting max fuel economy.
3) As indicated by the prior post, you can't adjust side to side.
4) I also found the adjustments in the different hole positions to be very minor to the point I couldn't tell the difference between lowest and highest position.
5) I never beached my boat but can't imagine it would be a big issue with the smart tabs. They don't hang that much lower than the hull bottom and when you beach your boat, you aren't likely going to have the entire bottom hull touching bottom or else you will not likely be able to get the boat out.
