3.0T Vs 2.5Bi-T

[Supra2NR]

question about twins

are the inline turbos the same size?
if not which one is bigger the front or back?
shouldnt they make a small and a big one

and does any company started making those variable turbos
bmw has developed that technology
it a big turbo with movable fins around the turbines
which closes in low speeds/rpm and opens in high speeds/rpm
so in low speeds it can spool up quickly without lag
and in high speeds it wont choke on exhaust