Me personally I would just toss the brother and get a newer inexpensive one for piecing and classes, they are so cheap that they are easily affordable, for the 1500 me personally I would look for a used babylock espire or quest plus because you can find one in that price range or even a brother qc1000, the newer versions would cost you around 1800 a new serenade(replaced quest) might still be in your budget, it is based of of a pfaff model with babylocks name on it, they are the IDT built in walking foot, If you get the espire or qc-1000 you can use your feet from your old machine. I have the espire and love mine very much, it has almost a 9 inch harp, but is very heavy(metal machine) I also hear extremely good things about the juki f600 and I would look at those, think they cost about 800 and have the strongest motors out there so I hear, that even surpass some more expensive machines