It's only in the last few months since I started quilting that I've even payed attention to thread. The quilt I'm making now is being pieced with Coats & Clark Dual Duty. I just looked, it's 100% poly. It looks and acts just like cotton to my untrained eye. It's also nothing like the monofilament thread used in cheap bedspreads. I've had the same experience with that stuff breaking and sticking out and would never use it (maybe the new stuff is better). I've had no problems with pressing the C&C thread I'm using. I guess time will tell about it cutting into the cotton cloth. I'm also wondering how UV resistant it is, that could be another weakness over time. I'll probably switch to cotton for future projects. I'm learning quickly that buying the small spools available in regular stores isn't very cost-effective when quilting. I want to switch to large spools or cones measured in thousands of yards instead.
Rodney