I agree with all the other comments. I also have purchased the Juki foot for FMQ. When mine was new, I had a little trouble getting the bobbin to sit properly in the machine and still occasionally get it in wrong. I used to use the cutter, but about every fifth time, it needed re-threading so I don't se tha much anymore. The other problem I have is that it goes like the wind and I like to FMQ a little slower, so there's a learning curve there.
I do a lot of charity quilting and they give me thread, and everything seems to work OK, even the cheaper stuff, but those require a lot more cleaning.