I have a Viking Sapphire 830 which I bought gently used. I have done over 150 quilts on this machine and love it. I can do up to a 120" x 120" FMQ and if you get the spring action open toe foot for quilting you can really zip along over the bumpy parts of your quilt. The only reason I would replace this machine is for something that goes faster. I can use any thread with it but have to increase the size of the needle with some thicker threads. I am so glad I bought this machine it has given me thousands of hours of piecing and FMQ with little trouble.