I have one of those 'fussy' machines. It used C&C and Gutterman only. Any serging thread I have tried has been a disaster. I'm sure I could use some of the higher end regular threads, but they aren't available locally. I will check our new LQS. The 'old' one carries Gutterman. Has C&C gone up? I have so many spools, I haven't had to purchase any in a long time.
Wooden spools - I saw a clear lamp base filled with them at JoAnn's Tuesday night. For people decorating in that genre, it was a great idea. I used to save my spools for attaching grippers and jeans snaps to apparel. The tools needed a wooden spool to work.