The Brother has an automatic thread cutter, the Janome does not.
I picked up both my machines second-hand from private parties. I paid $400 for my Janome. My DH bought the Brother with a New Joy frame for $400. The Brother looked like it had hardly been touched - not a scratch on it, no lint inside it anywhere.
You might consider checking with your local guild and quilt shops, you might find someone who wants to sell their machine.