Hi Leslee,
I had a Singer, Brother, have used a Viking frequently, and now have a Pfaff.
I love the Pfaff and bought it for the variety of stitches, the ability to embroider as well as the IDT, the integrated dual feed technology. All the bells and whistles are great, but I did NOT know that software to create your own embroidery or to do large patterns was an extra $2000! I don't really need it, but it would have been nice to know. Also, when I got it, it was a floor model so there wasn't a book or very much info with it. I had to learn by doing, researching online and badgering the life out of sewing center staff. One thing I really don't like is that the needle threader has broken TWICE - during the embroidery process, the plastic arm has snapped! True, the sewing center did replace it, but they make it seem as if it is my fault.
I understand it can be used with smaller grace frames for machine quilting but have yet to purchase one. If I had to do this purchase over again, I would really do more research and I think find a national brand with a close LOCAL store with ladies who are sewing experts - not just people hired by a company to pitch sales or guys who repair the machines and don't sew. My largest trouble has been not having a manual and the steep learning curve that came with learning embroidery. Hope this helps.