I also have a Janome and I have purchased some specialty feet: Bias Binding foot, Ruffler, Stitch in the Ditch, FMQ foot , Curve Master Foot and walking foot. First off, the bias binding foot was/is a joke. I have tried and tried to get it to work and I just can't do it (maybe operator error?) I have yet to use the Ruffler foot. I used the stitch in the ditch foot for a while for sewing on my bindings until I got better at them and I really prefer to use my Walking foot anyway when doing bindings. I use my FMQ (or darning foot) sporadically as I don't really care for FMQ on my machine. I have yet to use the Curve Master but there is a Drunkards Path in my future so I think it was a worthwhile purchase for me. My 2nd purchase of the Walking Foot was the best investment. I say 2nd because I bought a generic one from Nancy's Notions and I made it about 1/3 of the way through straight line quilting a lap quilt and it literally fell to pieces as I was using it. I then purchased the Janome walking foot and wouldn't be without it. I buy my feet here as well as other items and it is ALWAYS free shipping, no matter how much you spend. Their customer service is out of this world and they are great to work with, whether by internet or phone
http://www.kenssewingcenter.com/
If you don't have a Walking Foot, that would be my only recommendation for you.