Singer featherweight, newer model vs. older model

I am getting involved in quilting classes at my local quilting store
and am considering a lightweight machine to take to and from class.
I've been looking at the new featherweights, and see that they are 10
lbs., which is a "workable" weight. The question I have is, does
anyone know how many stitches per minute the machine does?

Also, if you have an older featherweight, 1950's type model, would you
happen to know the stitches per minute for that one? I am basing my
purchase on how fast the machines are. I could take my old Touch and
Sew, but that one's a little heavy.

Thanks for your help!