I have a Pfaff 7530 that I bought in 1999. It is a fantastic machine.
This past summer my husband bought me the Pfaff quilt expressions 4.0.
Both machines are fantastic. The 4.0 has made a real difference in my ability to free motion because it has that sensor feature. It has a wider throat for manipulating bigger quilts.
I love both machines. I had bad luck with two different Janomes, switched to Pfaff and wouldn't own any other brand.
I have a knowledgeable really good dealer which helps.
Pfaff rocks!