I agree it is totally possible to quilt big quilts on a DSM, but it took all the fun out of the job! I had made a baby quilt for a grand nephew that just called out for long, diagonal lines of quilting. A 54" long quilt, diagonally, is 70+ inches I was struggling to get under the throat of my Bernina 440, and it wasn't fun! I saw an ad for a Sweet 16, and started drooling. I ended up using a small inheritance from my mother to buy it (having never even tried it), and I think she would have approved! That was 4 years ago, and I am still love my machine. I tried out long-arms at the Nolting factory (lovely, helpful people!), but after a couple of hours I discovered I really prefer the feeling of fabric under my hands rather than handles.
Pam