As far as bobbin info?
201 takes standard bobbins, like 66 & 99.
The 301 takes featherweight bobbins.
I own both machines and my 201 sews through the many layers when I make the Bow Tuck purses.
I am still piecing my 301 together, but from what I have read it too is a workhorse. The 301 I have will drop the feed dogs.
Blessings,
Sandi