I have a Janome and a Pfaff CV. I use C&C and Connecting Threads mostly. I clean the bobbin area every time I change the bobbin...only takes a few seconds. I don't find any more lint on one brand than the others.
The main secret to keeping threads from breaking is proper tension settings and new thread. Old threads will break and fray no matter what the brand. Anything older than 3 or 4 years should be tossed. Just like those of us with old skin, the thread dries out. My skin tends to fray and break just like the thread!