As a fairly new owner of my Q'nique (love it!) since November, I have found proper tension is the key, and watching the speed also helps. I use either size 14 or 16 needles, depending on the weight of thread. Yesterday I was quilting on batik fabric for the first time on Q'nique. The thread broke a few times. Finally, I realized batik is rather tightly woven. I switched to a size 18 needle, and the thread breakage stopped. The needle does not leave any noticeable holes in the fabric.
Special note: before each project, I always test the tension on a strip of the same fabric on the backing next to the actual quilt top on the side and make adjustments accordingly.