" up to 10% more power, 30% more fuel economy, 50% better emissions " is claimed by the manufacturer of these carbs
personally I would be surprised if there is that much difference between a properly set up carb and a good fuel injection system if fitted to the same engine.
to be fair they look a well made item and they haven't been made down to a price , but these days a genuine 5% improvement is a big step as just about everything has been researched by the big manufacturers , and good new ideas are rare.
there are people on forums fitting these and saying they have made a big improvement, but maybe their old carb was worn/poorly jetted ?
hopefully i am wrong though, as 50% better emissions could help keep 2 strokes going for a few more years