In purchasing a machine to quilt, don't rush into anything until you have taken the time to research all your options.
The QBot software is interesting but it is very limited as far as robotic quilting is concerned. There are few designs available in the grand scheme of designs. I think most of the patterns are for no more than 8' blocks. Depending on the throat space available on the machine, generally you can count on no more than 8" of quilting space and usually less, meaning you are going to be required to move the quilt often to finish a block.
There are several other options out there. Many of the mid arm machine offer more throat space and frames that can handle larger block size in one pass. A mid arm is usually classified as a machine that has an arm anywhere from 12" inches to 18". If I were going to purchase a mid arm, depending on the budget, I would look at the Tin Lizzie's, some of the Noltings, the HQ16, the Innova 18" all of which would be close to the $5500 price range.
I was in the same boat, thinking that the machine I purchased 2 years ago would hold me and my Lady for life. It's a great sewing machine, a Bernina with a stitch regulator but for quilting as a serious hobbyist it leaves something to be desired. It will sew for the rest of my life but it's frustrating to quilt on. Even with a frame I have 4" of quilting area in a strip the width of the frame. It gets old quickly. If your wife has a good serviceable sewing machine, shop for a mid arm and ease your frustration before it sets in. I've been where you are and done that.
If you want some more information on machines and shopping for one PM me and I'll forward you some info. Our longarm comes home on Wednesday night.