I took the plundge this summer after moving my sewing room to the basement. I debated a long time about the pro and cons. For me, the no basting anymore was the main point. With three little ones, it was almost impossible to find the floor space to do it. I waited for the right deal and got it: a gently used HQ 16 on a frame for 2500$. I had to accept the fact that I would not use it for pantograph: the frame have to be against a wall. Even with this limitation, I'm so glad to have it! I enjoy quilting like I never did before. It's so easy and fun to draw big allover designs on my quilt! I would say the pros are:
-you don't have to baste your quilt
-finishing a quilt will take about 1\4 of the time
-not having to turn your quilt under your sewing machine make you feel free, you will use designs you never dare to think about before
The cons are:
-space! unless you have a very large house, the frame will take a space you would use for so many things...
-accessories: you need specific needles, bobbins, thread, etc. It add to the storage problem
-cost: it's an expensive toy... but you can shop for a gently used one, there is plenty of it
-it may not fit all your quilting need. I was thinking about selling my Juki Tl-98 to fund my HQ16, but I end up keeping it because I'm still using it for quilting. I prefer to do small detailed quilting design on it, it's easier. Also, loading a small baby quilt on the frame is not really worth it.
-learning curve: it was not a very big issue for me, I'm only an advanced beginner, so it was easy to learn new technique for free motion quilting. But I can imagine an advanced quilter not wanting to go back and learn everything again.
So, good luck to find the right solution for you! I had several months to think about it before we moved my sewing room, it helped to priorise my needs and desire.