I traded in my new Janome because it was a lemon that had been to the repair store many times and made a trip to the factory only to be told that it was in perfect working condition and must be "user error."  Now I have the Bernina 440 and the only complaints I have are that it doesn't warn me that the bobbin is low and I have to get my husband to come and take off the plastic tray as I don't have the strength to yank it off.  If I leave it on, I can hardly put in a new bobbin or clean the bobbin trace.  Otherwise, the machine hums right along and I've had no problems with tension or thread...