I have used quite a few different brands on my MC10000. Some I already had, some I've bought since getting the machine and a lot came with the machine. Black is the only color I've ever had any issue with and that includes RA. I have also found when I get near the end of a spool I can have some issues. All in all though I don't have many problems but I sure have a lot of fun. You will too. Have a good look around the internet before spending a fortune on designs. I like Embroidery Library and Adorable Applique but have picked up a lot of free designs that have worked wonderfully. Bunnycups is also a good site and they give their retired sets free.
You are about to embark on a wonderful journey. Enjoy.