We bought a Gammill because: The dealer was close enough to call for service, was reliable, and reputable.
After trying out several different machines, I was told: "Pick the one that controls the best for you." I had no idea what it was supposed to feel like, so that didn't help.
My husband's input was to look for the sturdiest hardware. The Gammill frame was the best design we found. One 8 hour day of class was included in the purchase. Before the class I was supposed to practice and get comfortable with the machine. That plus instructional videos was enough to "get me up and running".
Of course, I'm still learning techniques. I learn something new with every quilt completed.