2-stroke or 4-stroke?

[prodigit]

I also prefer a 150 (or tuned BBK 50cc) for round town riding.
I feel like my ATM50 is ALMOST enough for city riding, with one exception, is the acceleration between 20-35MPH.
Something a BBK could solve.

As far as MPG numbers on a 2stroke, it's kind of moot. A 2 stroke's fuel is a lot more expensive, due to the oil added to the fuel, thus can not compare to a 4 stroke.
If anything, if a 50cc 4 stroke gets 100MPG, a 2 stroke needs to get 125MPG to get even in fuel economy. A 150cc gets more than the power of a 2 stroke 50cc, while getting between 65-75MPG (85-95MPG for fuel injected). A 2 stroke 50cc would need to get at least 90-100MPG to beat the 150cc; $$ for $$ in fuel economy.

as far as reliability, it all depends on what brand, where made etc.
But under exactly the same conditions, a 2 stroker lasts less long than a 4 stroker.
Way more heat, runs way less efficient, and has way more wear.