I own two Bernina machines and I use what ever bobbin fits into the bobbin case. They work just fine. The same way with attachments, if the shank is not right, I use an adapter with the generic feet, etc. Their brand (Bernina) is expensive and they try to make you believe other brands won't work so you will buy theirs.

Mine are the large bobbins, too. My Bernina is an 820 but the bobbins hold at least 1 1/2 times what other bobbins hold.

I use only Bernina's

I have 8 machines, and three of those are berninas, the 830 LE has large bobbins, and cannot use any others, but the 145 and 550 both use the same size bernina bobbins. I would too afraid of some internal mechanical damage using another brand. The repairs are not worth the price, so I will stick with the bernina bobbins, although they are very expensive. I would also recommend to only use the brand for the bernina machines. OMGoodness, I was wondering how many bobbins in total I have....should have never counted them ..... 524 if the smaller bobbins, and 70 for the 830, didn't realise I had that much invested in bobbins......

I have an older Bernia---1030 (I think). I managed to screw up the bobbin casing and bought a generic one (the sales clerk talked me into trying it since the Bernia casing cost $50.) Anyway, the generic casing constantly broke the thread---about every 20 stitches or so. Frustrated as can be, I paid the price for an actual Bernina part and have been happy for many years now.

I use only Bernina bobbins in my sewing machines.

I only use Bernina bobbins in my machines. I have a 930 and 1031, why mess with perfection?
I've had problems with bobbins for other machines bought at Wal-mart or JoAnn's, so I've learned to avoid them. I'd bought some for my featherweight and the bobbin wasn't quite round and it got stuck in my bobbin case, thought I'd never get it to come out.
Sharon