Any reason...
Several.
The key question most people don't ask — 'is it reason enough for
me' and we obviously don't know that.
The ECG/EKG thing is nice, as is fall detection, even if you're not clumsy.
The S4 is 2mm bigger for either size 40/44 vs. 38/42 with a bigger screen, so it will be more legible for some.
It's slightly thinner, and some people have complained about the previous thickness. It's still a little on the thick side for some.
The corners are more rounded, given a more elegant look.
There's a new gold on stainless case that's gorgeous. It's far too early to tell how well that will hold up.
The digital crown uses Taptic/haptic feedback which I believe will make scrolling more accurate. It's also a sensor for the ECG. The ECG has the FDA's blessing.
New faces (or at least one) appear to have more complications available. Previous versions had too few for me. Some will complain about information overload, but they probably have trouble with a speedometer and radio. But you chose what you need to know, and it's more intelligently laid out. Some or all of that
may come with watchOS 5.
But it's pricey. It's $100/$200 more for the GPS/GPS+LTE version than the comparable Series 3.
Now this is where you state what's important and what isn't to you, that would have made responses more pointed and concise.
When a good man is hurt,
all who would be called good
must suffer with him.
You and I have memories longer than the road that stretches out ahead.
There is no safety for honest men
except by believing all possible evil
of evil men.
We don’t do focus groups. They just ensure that you don’t offend anyone, and produce bland inoffensive products. —Sir Jonathan Ive
Perfection is the enemy of progress. -Winston Churchill
-An armed society is a polite society.
And hope is a lousy defense.
You make me pull, I'll put you down.
Mister, that's a ten-gallon hat on a twenty-gallon head.
I *love* Sigs. It's Glocks I hate.