Quote Originally Posted by celluloidpropaganda

The first question - are the primes generally considered the equal of, say, consumer AF primes from Canon or Nikon?

The real question is are the pro Canon or Nikons close in quality to the best M42 lenses.

In addition to the lenses mentioned by the others.

Mamiya SX lenses. These were also rebadged and sold with a different mount for Rollei cameras.