As far as scratching are you guys talking about the case aluminum vs stainless steel scratching or the ion glass (basically gorilla glass) vs sapphire crystal scratching? Hard to tell from your posts.
The regular stainless steel case seems to be pretty scratch prone. A search on this forum will verify this. A few YouTube videos talk about it too. Though, you also do have the option of polishing those scratches right out.
The sapphire screen is extremely hard to scratch. It does shatter easier, but it seems more than likely that you'd drop it and shatter it before you scratch it. Ion-X glass can take drops somewhat better, but it will get scratches easier.
Aluminum casing on the sport doesn't scratch as easily as stainless steel, but it can still scratch, just like that.
As for the casing on the black stainless steel, there's very few who say they've damaged the watch at all. Did a search the other day and most people who had anything to say about it were talking about the bracelet. I only recall seeing 3 cases of damaged casing, and one of them had a shattered display too. It seems the only cosmetic issues that are happening is if the DLC gets busted through, and the regular stainless steel is showing or something is hit hard enough that the material deposits on the coating.
I can't wait to see a test where somebody seriously takes the thing to the limit.
Either way though, if I couldn't have the black SS, I'd take the regular SS before I take a sport. I'm not even talking about fashion-wise. It seems they'd end up looking better over time.