What you are considering is not just an upgrade, it's a complete change in the way you quilt. It's very different to move a big machine around on a carriage, versus moving a quilt under a stationary needle. You should find a friend with a longarm or rent one that you can quilt one of your quilts on. Or go to a class, to see if you actually like long arm quilting in a frame. The difference is much more than sitting versus standing.