In the 90's we owned a C-30 with a Yanmar YSB-12, 1 more HP than 5411 or virtually identical, it worked but was pretty anemic. I installed a field cut-off for the alt, to take it off line when we needed to, and this gave a bit more power. I also went to a properly sized three blade prop from the two blade. Properly sized meant we could attain max rated RPM, digital tachometer confirmed, and this took a re-pitch to get just right. After going from the two to three blade the boat was perfectly usable, even in Maine with our 11' + tides. Usable does not mean fast however...
A buddy who owns a boat yard had a customer walk out on a stored boat in the middle of a re-fit. After his lawyer cleared the sale of the boat, I purchased the new, still on a pallet & yet to be installed Universal M3-20B. I got the engine for $1650 after I sold the boat for him to recoup the owed yard & storage fees.
The M3-20B certainly would not have been my first choice, but a brand new engine and gear for $1650.00, well, you just jump on it and ask questions later. Even the difference between the YSB-12 and M3-20B was night and day.
I suspect the 5411, propped right (many boats are not) is still a decent engine for that boat, but not if you want to go fast...