A new project: Big Dots

Finally, I've carved out a day at home to sew.  I'm treating myself with beginning a new project, a baby quilt that will be called for next month.  I'm going to do "Big Dots" from Quilts Made Modern, a new book by Weeks Ringle and Bill Kerr of FunQuilts.  The quilt will be about 20 big circles appliqued onto a solid field.  I decided to use some of the hand-dyed fabric I made up this summer for the dots (rust to navy above), but I didn't have a large piece of an appropriate color for the field.  I decided to dye up a new piece for this, choosing a pale peachy orange from the sample book from Carol Soderlund's class.  I was dubious about whether this would work, because one is always told that dye needs 70 degrees or warmer to bond with the fabric, and I don't keep my house that warm.  Some people warm up the container by putting it on a heating pad, but I didn't want to bother with that.  Frieda Anderson, who taught at my local guild in October, had encouraged me not to worry about the temperature--she dyes through the winter in her basement, which is definitely not 70 degrees.  So I went ahead and tried it out, and it worked beautifully.  The resulting color is perhaps a slight bit paler than the sample I was aiming for, but that's perfectly fine for this project.  Success!

The directions for this project recommend machine applique for the dots (about 7" and 9" in diameter).  I've always done needle-turn hand applique before, but decided to challenge myself and learn the technique recommended in the book, which involves using freezer paper templates, basting around the edge and pulling the thread ends to turn under the edge, and then using  zig-zag stitch on the machine to sew the dot to the field. The "freezer paper and pull-the-thread" technique is quite nifty, and gives a really smooth edge. Here's a sample I did with some other fabrics. 

I tried two different machine stitches.  To the left of the arrow is a blind-hem stitch; to the right is a narrow zig zag.

I'm not sure which I prefer.  The zigzag lays a little flatter, but the blind stitch is less visible (except for that run of stitches around the outside of the circle).  Of course I could make it really invisible by switching to hand-stitching.  Any advice on which you think looks better?  I'll also be machine stitching the quilt once it's put together, so that will be another layer of stitching.