No, because it's not only a 2 stroke, but also carbs cannot adjust for air pressure/temp/etc.
How in depth of an explanation do you want
we can get into engine temp, air temp, manifold pressure, carbs 'inject' (well, the engine sucks in) the air/fuel/oil below the pistons into the crank. where the DI would only inject above the piston. resulting in less fuel going out the exhaust. and no fuel going into the crank...
I'm no expert, there's way more to it than I'll ever know... but I do enjoy learning about engines... even though they are old school lol.
DI/EFI/Etc is better. period. however, these aren't brand new any more.
These parts are 20 years old. the fuel pump ($$) the injectors, computers, etc. all 20+ years old... If you got 20 years out of anything, you did good.
However, carb ones are easier to work on, cheaper to fix, and mechanically simpler, thus usually more reliable. The actual fuel save, I can't image being more than a few bucks a season, and that's if you run a lot...
if you like learning about car parts, this guy has some good videos
https://www.youtube.com/user/EngineeringExplained/videos
Also, you posted Carb 951 vs. 951 DI, but you also referenced the RFI. (DI and RFI are not the same).
The RFI skis were 787s, and I am told they are fairly reliable. I believe they were 110HP.
The DI ones, not as much. (well, not after 20 years).
I freakin loved it but you gotta be good mechanical to own one. Nobody wants to work on them. I still haven't made a rig to test the fuel and air pressure.
