I think your story is really a word to the wise for anyone looking at buying expensive machines. If the main purpose of owning the machine is quilting, it might make more sense to have a less expensive workhorse sewing machine and a sit-down longarm quilter.
A longarm is fabulous if you can afford it. I have one on a frame. (I purchased it used in 1996 and don't plan on ever buying another one. It is huge, has a 30 inch arm, which is almost a detriment sometimes, but sometimes AWESOME!). I have been looking at the feasibility of modifying it to work as a sit-down quilter (while still keeping it capable of working off the rails).
I am a free motion quilter, almost entirely. I will draw out my designs sometimes before quilting, but I don't like pantographs or perfect circles, etc. They all looks store-bought to me. Anyway, my experience with free motion quilting on my DSM and on the longarm is that I get more control on a sit down quilter, where I'm driving the quilt, can quilt a long angular line at once, or rotate to get in the perfect position to do some special motif or whatever. I get a flatter quilt on the frame/rails. That and I don't have to baste the quilt if it's going on the frame. But to use many of the stencils, pantographs, etc, the frame is probably better.