David, use the coupons at Joann's and get some new ones!! Doesn't seem like there is any correct answer and everyone has different opinions. I also have a Brother and some old metal bobbins from my old Singer, so I use plastic in the Brother and use my old metal ones for "thread on the go" so I don't have to lug spools with me to do a little sewing away from home. Those spare bobbins fit nicely in those clear plastic pill dispensers (the daily/weekly ones) or like I bought at Joann's, one that has a spring lock bar so they don't accidently open. It was only a couple of dollars and I still used a 20% off coupon and each compartment fits two bobbins.