You will probably get along ok with threads suggested on a log cabin. But I prefer ordering Presencia Brand 60 weight thread (which is finer) online from Red Rock Threads. This brand also comes in 50 weight so be sure to check you are getting the right thread. It may not seem like it but thread can create a lot of bulk in the seam, especially if several of them come together. I buy the thread on cones in grey, black, beige and white. Then I just sit the cone on a thread stand behind my machine.

I quilt mostly with Coats and Clark quilting thread, says so on the spool.