The snap-on feet should work if you use them with the correct Bernina adapter. Try them out carefully (I would use hand wheel at first, then sew slowly) to make sure they perform as you want. That's actually the purpose of the Bernina adapters -- to allow you to use generic feet and feet from other machines with your Bernina.
It's probably not an issue since you have an older Bernina, but watch and see if the snap on foot covers the feed dogs. If the foot is smaller than the feed dogs, it probably won't feed the fabric very well. Older Berninas usually have standard width feed dogs, so I don't think that would be a problem.
Last edited by Prism99; 09-27-2013 at 08:55 AM.