I only use the button on the embroidery machine...
On regular piecing or quilting I prefer the foot controller. My machine also has a red square next to the foot controller so that you can touch it and cut your thread. I had to disconnect it from my machine...as I have a cute little dog named Tinkerbelle who likes to plant her fat little butt right on the red button.
She kept cutting the threads on me all thru a seam...until I figured it out....figured the machine was going crazy!