It differs in case material, color, dial material and design, as well as weight and size. This is a major departure from the regular Speedmaster, and it is executed almost perfectly in all aspects.
Omega Ceramic
The most striking aspect of the Grey Side of the Moon is the contrasting color that Omega has achieved in ceramic, and how uniquely it pairs with the platinum tones of the dial. In a way, it looks as if the dial has a tint of lunar dust or perhaps some kind of moonstone - if you check the stock images on Omega's website, you will see this watch against a moonstone background, showcasing its resemblance. In reality, as I hold them here, they completely match what Omega aimed to create and demonstrate in their promotional materials.
This Grey Side of the Moon features a fully ceramic case, crafted from a solid block of ceramic, similar to how the Rolex Oyster case is made. It beautifully shimmers and changes shades of gray depending on the lighting. The dial is clean and classic, without any of the fancy patterns we sometimes see on Speedmaster watches. It features a dual sub-dial layout instead of the traditional three, and has a well-placed date window at the 6 o'clock position.
Crown and Pushers
These watches truly look very attractive, with functional design executed in an eye-pleasing style. You will notice the signature contoured and curved lugs of the Speedmaster, though short, providing comfortable wear. You will also notice the recessed pushers and crown on the side, providing additional protection while looking appealing, without the need for large, bulky, and sometimes unsightly crown guards.
Movement and Wearability
Flip the watch over, and anyone could write a novel about it: for your pleasure, the Omega 9300 caliber is visible through the exhibition back. This is a self-winding chronograph movement with a column wheel and a co-axial escapement. This movement is easy to admire, and its finishing is unparalleled in its price category.
The only drawback I see with this watch is its size - 44.25 mm, although the short lugs make it wear much smaller than it seems, it still is better suited for those with at least medium or large wrists. The chronograph movement, though an absolute marvel of engineering, also has significant thickness, making the watch overall a bit thick on the wrist. If you are a Speedmaster collector or want to get into Speedmaster, this watch can be a great acquisition for you, though it is hard to say how long Omega will continue to produce this model.