I'm just wondering why Apple is using "Ion-X" glass on its sports model, when they say in the same paragraph that Sapphire is the strongest glass ever? The steel and gold models use sapphire. On most Apple Watch models, the display is laminated to a machined and polished single crystal of sapphire. Next to diamond, it’s the hardest transparent material. On watches in the Sport collection, protection is provided by strengthened Ion-X glass. (from here). I would have thought that especially a sports watch would have benefited from strong glass as you'll be excercising with it. More likely to be banging into stuff. That makes aluminium a weird choice too as it's also much more fragile than steel. This might impact my decision which one to get - the stainless steel looks better in my opinion but is bound to be heavier. But if the sports one is more prone to scratches it makes it a hard decision. I wonder if the sports model would actually be the cheapest one?