I have a Performance 5.0 and love it, I traded in my Ambition 1 for it. I also own a Select 3, my first Pfaff, which I use and take to class most of the time. I chose Pfaff because of the built in IDT dual feed which for me was a must as I make teddy bears and a regular walking foot made it hard to get into all the small curves. I am just getting into using alot of the features that are on my 5.0 mostly because I discovered a website which features mastering your sewing machine;
www.sewingmastery.com. There are 60+ videos on using the Pfaff 5.2 (which is same as 5.0) and goes into detail on everything from setting up machine, threading, stitches and more. I do take my machine in yearly to have a cleaning/maintenance check up, I do clean the bobbin area when starting a new project or doing a lot of fmq as it really tends to collect dust bunnies. I do stop and rethread bobbin and machine and clean bobbin area if machine starts to skip stitches or have problem of eyelashes when fmq, automatically do it as if I only rethread or play with bobbin I end up doing both anyway. Conclusion is I love my Performance 5.0 and my Select 3, I can't see myself purchasing another brand of machine.