I have a Tin Lizzie 18LS that I purchased last spring. I love it! Any problems I have had (which are few) have been operator error. I don't have QBot, so it's just me. I have done one quilt using a pantograph and working from the back fo the machine. It worked very well. The rest of the quilts I've done (about 6) have been done working from the front doing free motion. I love doing free motion. I have a lot to learn, but I am making progress. : ) I can't speak to the APQS or the Gammill. I've never worked with them. Good luck with your decision. I hope you're very happy with whatever you decide to buy.
Kerry in WA