The lower end Berninas aren't Berninas, they're Bernettes. And there is a big difference. The lowest price on those is the Sevile 46, for $149. I actually like the Bernette London 5 -- which is advertised for $399 in the Bernina Christmas sales promotion (but your dealer will probably sell it for a lot less). I like that it has an oscillating, all metal bobbin/hook system. You get some great stitches, including the blanket stitch for applique. There's a buttonhole system, and you have control of the stitch width, which you don't on a lot of lower end machines.
I did get a cheap Brother machine in the shop today. She paid about $80 for it (about 1 1/2 years ago), and the timing was off. I took the needle plate off to see what timing setting was off, and the thing had a plastic hook!!!! I told her to throw it away, it wasn't worth fixing.