Let's get real—the Moto 360 Sport has not been a successful device for Motorola. It took too long to launch, was too expensive, and didn't look or feel very nice. The original $300 price is in the rear view mirror, and now it's reached an all-time low of $161.32 on Amazon. At that price, I think it's a reasonable purchase.
The 360 Sport is (obviously) aimed at fitness applications with the silicon band and transflective display. There's also a heart rate sensor and GPS built-in. While the device comes in one of three colors, and the straps are non-replaceable, only the black 360 Sport is included in this deal. The other versions are still $199, which appears to be the default price these days.
The black 360 Sport is in stock and has Prime shipping. This isn't part of a lightning deal or anything, so you don't have to jump on it immediately. However, I doubt it'll stay at this price too long.