aborning, I have an old Pfaff 7510 (made in Germany) that I use when I'm quilting layers. (And I also have a Bernina Artista 730 as well as a new Brother that doesn't even compare to the Pfaff when quilting layers, even with the attachment of a walking foot.)
I love this machine so much, and since it's going on 20 years old, I worry that it will break. I recently stopped in the local Pfaff dealer and discussed a replacement machine. They told me that the new IDT system is not as good as the old ones. They showed me a brand new model "that
has the old IDT system" that I should consider. It's the
Pfaff Passport 2, and weight 12.9 lbs. It was designed just for quilters.
http://www.youtube.com/watch?v=bmzbvYGkZEQ
I haven't researched and confirmed this information, but it might be something you want to investigate.
Good luck on your decision, let us know what you end up with.