I bought a tutto (large size or X-large) on wheels to port my Bernina QE440 machine to classes. It steers beautifully, has multiple pockets and connectors with strap in both outside pockets so I can strap extra bags on top.
I love it as well as the machine. I also have a small inexpensive Brother 6000i that I can take to classes where I'm mostly straight stitching or zigzagging.