I don’t mean scratches on the case, nor am I comparing the glass to sapphire; I can’t find anything that speaks to improvements in the glass material on one series to another beyond Ion vs Ion-X.
I doubt the screen durability has changed much from S4 to S7. Some people, myself included, are just prone to scratching watch screens. I've scratched the screens of every watch I've ever owned. So I always use screen protectors with my Apple Watch. You can get them on Amazon for less that $10.
For me, it's a resounding no, lol. I put on a $10 screen protector, and I'm good to go.
But the stainless steel might be worth it if you wear it to business or dressy occasions. It does look nicer with the more dressy bands. Completely depends on your situation and how/where you wear the watch.
I've got a pretty scratched up Series 4 aluminum and have had it since release in 2018. Apple has boasted about having a more durable display on the Series 7, despite it being the same Ion-X Glass used back in 2018 on my series 4. Is there any way the new version improves the durability and/or resistance to scratches?
I considered the stainless steel model but it's 70% more expensive than the aluminum and I'm not sure that it's worth it.
S7 is more crack resistant but I’m not aware of any improvement regarding stratch resistance. The best improvement you can make is to buy Stainless Steel or Titanium with sapphire screen. But yeah, it’s way more expensive.