This is not a question on which thread to use when/where but a question on age of thread.
I've heard not to use "old" thread. I've bought thread "new" at stores and it unravels, leaves a lot of lint, doesn't sew right or breaks continuously. (Yes, I had it threaded correctly.) And I don't buy inexpensive thread.
As soon as I changed the tread, my machine (a Baby Lock) worked perfectly. This could have been the same color, same thread, bought at the same time! When I put the "bad" spool back on, same problems.
How can you tell if thread is too old (or just bad)? How old is too old?