I've got a Rolex GMT Master II I've had for 21 years. The stainless steel shows some minor scratches and the sapphire crystal is like the day I bought it. 

Yes it'll scratch but not as easily as iPod touch, etc.
You would think no one had ever made a watch out of stainless steel before the Apple Watch.![]()
Yes SS will scratch and will have a ton of fingerprints on that shiny finish, that's why I'm getting the Sport.
Guess what? The Sport will scratch too.
What? SS all the way. Al is boring and kinda ugly and you can't polish it. No serious watchmaker uses it.Aluminum is a better material than stainless steel, so I don't understand why you prefer SS.
I have a stainless steel watch with a sapphire crystal. I have scratches on both the steel and the sapphire. Don't expect miracles just because its Apple.
I've got a Tissot stainless steel and sapphire crystal watch. The SS is scratched all around the watch face, but the sapphire is as good as the day I got it - 8 years ago. I'm a bit clumsy perhaps, so my watch has been banged up against brick walls, scratched on concrete, etc. and whilst the SS is now 'burnished', the sapphire is unbelievably scratch free. Still amazes me how it survives...
needless to say, I'm considering the SS Apple Watch and not the aluminium sports edition...
What? SS all the way. Al is boring and kinda ugly and you can't polish it. No serious watchmaker uses it.
SS looks better, it feels better (heavier) and it's more scratch resistant. And the most important thing, it can be polished so all the scratches disappear.
I'll take white gold or platinum every day over SS, though.
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It's almost impossible to scratch sapphire crystal. Believe me, i tried everything: a steel/titanium screwdriver, keys, knife, even rubbing the watch against a brick wall. No scratches.
Only diamond can scratch it.
BTW, some watches have an anti-reflective coating on the crystal. Well, that can be scratched, but not the glass itself.
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Yeah, sapphire crystal is tough. I wouldn't buy a watch whitout it.
If you really like your Tissot and plan to keep it for a long time, you should service it and ask for a polish as well. It will look and run like new.
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Wow like new, hope apple does something like this![]()
I have a iPod Touch 3 with SS back, and personally I prefer the aluminum back of my iPhone 5S.
Aluminum is a better material than stainless steel, so I don't understand why you prefer SS.
The ONLY thing better about aluminum is that it's lighter, unless you're a machinist, then is also easier to machine. SS is a better material in every other way.
How many of you SS watch wearers have already noticed scratches on the case?
This is the reality of SS watches. I have quite a few watches, and the SS ones have a lot of scratches.
In addition to the previous post:
To keep stainless steel polished and stain free, many people swear by Cape Cod Polishing clothes, which you can buy off Amazon and perhaps even locally at a hardward store.
For taking care of scratches, you might also want to look at my post here, using a different method with nail polishing files available at your local pharmacy.