I know one dealer that sells Brother, Pfaff and Janome. The daughter that teaches the embroidery and quilting and just a know it all when it comes to sewing also knows all the ins and outs on how to use all three of these brands. She said she tried a Bernina and found it not to be as user friendly as the other makes.
My cousin in another town is friends with a church member who works part time in a LQS that also sells Brothers and Berninas. She owns the big Brother Quattro, said the Berninas are not as user friendly.
Know another owner of a LQS in a small town that does NOT sell machines. She made a trade with her sister; sister took her Bernina and she now has sis's Viking. I told her what two other dealers said about Berninas and she said she has heard the same thing from others that come in the store for classes, etc. She said if she did ever go into the selling of sewing machines she would do Viking and Pfaff.
So these are just some opinions from dealers and mentors that have used all of the above.