Some thoughts from an engineer working to keep generator exhaust clean......
"The impact of diesel fuel sulfur content on particulate matter production is very well documented and has been for years. Sulfur content has a large effect on lube oil life, exhaust system corrosion, exhaust smell, and hull cleanliness.
Our SeaClean emissions control system is engineered to account for fuel sulfur content and the amount of time the boat will spend in regions of the world where fuel may be suspect in order to reduce damage caused by sulfur. There are areas in the Caribbean and eastern Med where the bunker receipts cannot be trusted to reflect actual sulfur content.
The reason lube oil becomes dark is because of soot loading. Higher sulfur content fuel nearly exponentially increases soot production. For that reason alone it is critical to use a higher base number lube oil or change oil more often when using high sulfur fuel.
If the boat only operates in US waters or fuels from "first world" European sources as most readers of the forum, it is not an issue. "