You've been given good advice so far. I have 2 old 1970 something model Singers that run really well and do piecing just fine. I can actually quilt pretty well with them also. I decided that I wanted more types of stitches and a stitch regulator.....so I found a used top of the line Bernina last summer and I've never looked back. Now if I can just stop buying fabric long enough to buy a couple more of those expensive feet :roll:
Just make sure you sit and sew to test drive BEFORE you buy..my dealer let me bring the Bernina home for a few days to try it out. I thought that was a really good sign of a good dealer.