Both brands make excellent machines. I myself am a Pfaff fan. I bought my first(a 2058) many moons ago and fell in love with the IDT. A few years later, I bought a 2170 which also has an embroidery unit. I just recently purchased a Creative 2.0 used - it has the larger harp.
All that being said - I am a great fan for lists. Make a list of which features fall into the must have category for you. Identify and try out, if you can, those features on machines of both brands that fill that list. Sometimes while machines can do the same thing, one machine might be easier or more intuitive. Then look at price.
I am assuming that you are looking at new machines at dealers. Please remember that ALL sewing machine prices are negotiable. I used to sell Viking/Husqvarna sewing machines and was amazed at the "wiggle room" in the listed price. If they will not come down on the price - then ask what else would they be willing to add into the package that would make the deal more attractive to you. If you are only quilting than an acrylic table might be of use, if you are embroidering - than maybe designs? Do not hesitate to negotiate - good luck with your quest