red
Yep that is my vote

Another red vote here! Very pretty quilt.

I think red would be best

I vote for RED binding for sure!

Red to accentuate the inner red border!

Auddtion the colors. I think that the red may be too bright and pull your eyes to the red and away from the inner quilt blocks. Actually I vote for blue

red is not my colour , but, I do agree the red will work just fine, it will make the quilt pop!!
good luck.

I say Red to match the inside red and to help it really stand out.

I'd say red, but if you do the flange binding, I'd put yellow inside with red. I've done the flange binding once, not hard, and it looks really nice.

Definitely Red.