It's all a matter of preference and perspective.
a) Take 2 hours to load a quilt on the frame and save time quilting it with a longarm. Total time for an all over design - 4 hours.
b) Take the time to pin it all together on the floor and quilt it on your DSM. Total time for an all over design - More than 1 day.
c) Take the time to load it on a hand quilting frame and hand quilt it. Total time for an all over design - More than a week.
No matter how you look at it, it is a much shorter time to finish quilting on a longarm. Me personally, I'll keep my frame and avoid all that pinning time.