I have two Berninas the quilters edition 550, which is a workhorse, it has the Bernina Stitch Regulator (BSR) which I find very helpful. I have had it for about 2 years now, and very very happy with the performance and maintenance of this quality machine. It is very easy to use, and has many stitches if you would like to utilize those, they are very easy to access and stitch up very nice. It has a larger throat for quilting, and I have FMQ on many since I purchased sane.
There is only one problem with the bernina, if the tension goes all to heck, all you need to do is to rethread top thread and that will probably solve the issues. Easy fix for those issues, which are rare. I have a Janome as well, and I don't like it for quilting - the bobbin doesn't like to FMQ, I was told it is the bobbin laying on its side which causes those issues.
I also own the Bernina 830 LE, however I wouldn't recommend you touch this one, as it has a big learning curve and none of the other bernina bobbins will work in this machine, the bobbins are larger. Best of Luck in your search for the right one for you!!