I think a reed tuned RT is very different to a piston ported one.
My RT230 reed with ex-box and phbh30 goes very well (my speedo reeds 0mph at all speeds). I can keep up with and pass motorway traffic. It has a very linear power delivery, almost like a 4 stroke.
My other lambretta has a piston ported RT210 (RT195 with 62 stroke crank, casa clubman and phbl25 through drilled airbox). This feels very similar, but not as fast motorways.
In a nutshell, what I'm saying is that although they feel the same in power delivery, the reed version is a lot quicker.
But maybe the biggest difference is the carb?
And also maybe I just confused matters
