classes mostly, my big machine is heavy so don't use it for classes unless its and embroidery or FMQ class. I also use my small machine for travel when I go to my inlaws house and take it to sew. Also there when your machine is in for servicing/cleaning to use on current projects. It is always good to have a back up even if it is not used that often. I also used to keep my mechanical out with a walking foot on so I didn't have to spend the time putting one on my big machine before I packed it away for my daughter