Quilt #27 & Thread Recommendations

This is quilt #27.  These Jumbo-sized blocks were made using old shirts.  I love the shadowed 3-D effect it has!

I quilted feathers in the border, a vine of leaves in the black border and over-all swirls in the center.  I used grey Aurifil thread on top and Connecting Threads Silver Essential Pro in the bobbin.  They seem to work well together for me-they are very similar in color and thickness.  I really like Aurifil thread, but it is much more expensive, which is why I used the Essential Pro in the bobbin. 

You can see in more detail from the back.  I did change thread color in the black border to match.  Anyone have any thread preferences out there?  What breaks more than others?  I'd love to hear about it!