One strong consideration, for me at least, is dealer support and lessons on the use of the machine. When I bought the Pfaff 7570 (back when it was just released), I chose a dealer who offered several weeks of classes for free to anyone who bought their machine from her. (She had done the same thing when I previously bought the then newly released Pfaff 7550.)
No way would I have learned to use all features of these machines without the training. She is an excellent teacher.
A couple of times she brought in well-known Pfaff trainers from other parts of the country. That was when I met dear Phillip Pepper.