I myself am very partial to Pfaffs. I sold Vikings 13 yo but bought a Pfaff (which didn't go well with my boss lol). I started with a 2058 then bought a 2170 embroidery / sewing machine. Later I wanted larger harp and bought a Creative 2.0 and now am sewing on a Creative 4.0.
I purchased the Pfaff for the built in walking foot (they call it the IDT system). One thing is all the feet I have ever purchased for any of these machines fit all the others. All these Pfaffs were used machines - one first one was from a dealer the others found and purchased off craigslist.
All the dealers you listed carry good quality machines. My list of "must haves" for piecing machines is needle up and needle down, ability to move the needle position left and right, built in walking foot, a straight stitch needle plate with an option to lock the needle from moving left to right and a variety of stitches. A lot of machines have built in alphabets. I have a long arm so if you are looking for a machine for free motion I have no recommendations for a machine there. One other question you need to answer is are you interested in a machine that embroiders as well as sews?
I would take time and go to all three dealers and sew on every machine available (new and used imho).- take notes on the ones you like and if you decide on one do not hesitate to negotiate. For a lot of dealers, while the price might be non negotiable, they may be willing to throw in extra feet (a new 1/4 foot maybe, welting foot, ..... etc ) and other items to make the sale. If you are a confident sewer and comfortable with machines you could look at used machines as well.
Good luck with your choice!!