I have 2 brother machines which I absolutely love. I also have an older Janome machine that is a workhorse but is pretty much a basic machine. There are several Brother machines that are reasonably priced and also Janome's. If there is a Brother dealer near you they often have very good bargains on used machines. You could pick up a good machine for $500 to $600 new and used even better. I have never had maintenance problems with my machines.
I have no experience with a Pfaff; but I agree that Berninas are way over priced.