Out of curiosity, how does it behave in reverse? I am thinking about a trolling plate for my pontoon.
With the plate all the way down it backs up poorly, over steering and over correcting... With my boat/prop/plate combo, the boat will crawl up to a dock if the plate is full down, just hope there isn't any breeze or current as the boat control is almost non existent.
That's the main reason why I made the metal cable lanyard I mentioned, the lanyard holds the plate up about 30 degrees off full down and allows the prop more clean water. It makes backing up easier and brings the trolling speed up off a dead crawl. The lanyard clips to the swim platform's back edge (then down to the center of the plate) so the lanyard wouldn't work unless you have a stout swim platform over the prop...
I bought the Troll-a-Matic so I didn't have to worry about raising the plate before throttling up/planing, but the disadvantage is it's always trying to go down. Manual (or locking) plates can be bent if you forget to raise them before planing, but once raised the boat's handling is normal. Advantages and disadvantages to both types.