Definitely the sport loop. And definitely get them from Amazon. I have this one in Alaskan Blue and Khaki, and I have Apple’s own Midnight Blue.
Yes, if I set them side by side, I can tell the difference — Apple’s is a slightly tighter, sturdier weave. But the Amazon knockoff is very good; it looks great and is comfortable. And at $10 or less (it’s gone down in price since I bought it), it’s a much better deal than Apple’s $49.
Don’t get me wrong. I love the Apple band. But if I can get something that’s very nearly as good for 1/5 the price…