If you are just looking for a machine to quilt and straight stitch with, then I suggest a Juki TL98Q. About $800.
I have a Bernina 640 emb/sewing combo. Got a super deal on it (brand new) because I had a trade in and Bernina was offering a special and so was my shop at the time! They run about $6,000 but I didn't pay that.
The bad thing about Bernina's is that only a Bernina tech can work on it if you want you warranty to stay good. Bernina shops are hard to find. Luckily I have one close by but they are soooo slow at ordering but do have a good tech who is certified to work on Bernina's.
Also Bernina feet are EXPENSIVE!!
I heard babylock & brother are good machines. Good luck with your search.