Well, I love my Bernina 1230 but it is something like 15 years old and not made anymore. Not sure I could afford a new Bernina at their current prices. Whatever you do, don't get a Bernette!!! If you can't afford a Bernina, there are other brands of sewing machine much better than the Bernette.
I would also definitely recommend against getting any Singer machine. The vintage Singer machines are wonderful, but Singer is not a good brand for machines nowadays.
A lot of people like Babylock. The straight-stitch Juki is very popular among quilters for piecing and machine quilting. For me, the straight-stitch Juki would not be enough if it were the only machine I had, as I wouldn't be able to do machine applique with it (I want zigzag and a few specialty stitches for that!).
It's best to first decide on your budget, as that will eliminate a lot of machines. Then make a list of features you definitely want. For me, needle-down is a necessity for piecing and quilting! Aside from some specialty stitches, I would also really like a machine that would be able to stitch out labels for me. (Although theoretically my old Bernina can do this because it has an alphabet; in reality it's very difficult to get an entire line printed out correctly and neatly -- at least by me.)