Hi all, I didn't read the entire thread so forgive me if I didn't catch something after page 1.
I have a 99 Hewes LT with 150 (54 mph with load) and went through many plastic cheese graters before the SS model came out. I posted a few threads on the original forum about this. When the 2nd one broke I really looked at how it broke and it seemed that it was over pressuring and broke from the inside out. After the third plastic one broke I ran without a grater (just removed all the broke pieces and put the 6 screws back in) for some time, actually until the SS one came out. My experience on my boat running fresh water canals and I did not see performance difference. The only difference I saw was that if I was in seaweed or weedy fresh water, the flow to livewells would clog. This only happened a few times and for all but one time getting on plane for awhile cleared the blockage. The one time I had to backwash to clear as weeds got into the lines. I've had no issues with the SS grater.
A 16' with a 115 could have a different experience than my boat so I'm not doubting anything just telling my experience. Also I did not try a grater with less holes (more streamlined) so I can't comment on those improvements.
I would say if you want to see a difference on your boat is to go run it in calm water with the grater, then with holes covered and then take it out completely and run to see the difference of the 3 modes. I think many of the old timers still miss the original forum content as there was a ton of great info there.