I have a 2003 opti 200 and have ran it for 4 seasons. bought it used from Alpine morrison marine in Saanichton so i can testify as an actual owner. These are two stroke direct injected engines, (fuel is injected directly into the cylinder head along with compressed air) run very clean, no blue smoke at start up, start right up, with tons of power and great power/weight , and yes the fuel economy is awesome. I have had no issues with it so far but it does get flushed and cleaned every trip.
If your looking at used one, ask for the computer print out. It will tell you how many hours at the different rpms it has run and if it has thrown any codes for problems.
There were issues with the earlier versions but they were all ironed out by 2003, i think it was mainly injector problems.