My two cents worth....I have a Bernina 430, which is pretty much the same machine as the 440. It's my only machine. It has done everything I've asked of it....thick seams, heavy fabrics, multiple layers, sheer fabrics, quilting, home dec sewing, you name it. It handles everything easily and has a beautiful straight stitch which can be even better my adding the straight stitch throat plate. I "upgraded" by buying a second-hand, hardly-used BSR for half of what a new one costs. It works wonderfully....I just need more practice at making pretty designs with it!
I did buy several extra feet that I now realize I won't use very often and could have done without them just fine. The walking foot is an essential for quilting and I've heard reports that it is more reliable and easier (therefore cheaper) to repair or adjust, if necessary. To me, the more bells and whistles that are included on the machine itself, the more things there are to go wrong someday...sort of like a car!
It all comes down to how the machines feel to you...keep test-driving and pushing them to do the things you want them to do.
AnitaSt