This website may help with your decision
https://sewingmastery.com. She runs through everything you could want to know about the Opal 650, Jade 20 and Ambition 620. I'm a Pfaff person myself, I love the IDT system, currently have a Select 3.0 (backup), Passport 2.0 (travel) and the Performance 5.0 (favorite). Whatever you choose enjoy.