TCW3 oil is for water cooled 2 cycle engines and is ashless, many guys here swear by it. Lucas UCL gets some good reviews too, but is almost twice the cost of MMO or TCW3, so I shy away from it. What I like about MMO is it does some cleaning, is a great top oil, and attacks and prevents carbon buildup.
If you decide to use MMO I would suggest using it this way: First get a good FI cleaner like Techron, Regane, or Amsoil's PI. I would run one of these cleaners as per instructions just before an oil change. Then once you've run that tank down, start using the MMO. The MMO will act like a top oil, and keep everything nice and clean. The good news is once everything is clean from one of the cleaners I mentioned, it will stay that way. It also lubes the injector tips and helps to maintain the spray pattern. I got this information from Mr. Kelly the MMO tech over at Turtle Wax.
HTH,
Frank D