If I’m new to Apple Watch, with the 700rm difference, go UW or UW2 better?

Thanks, I guess will go for UW1 for now. Save some money. Hehe.

So I have been using the watch for about 1 month now, and notice the skin directly under the sensor have discolouration and peeling when dried.
It doesn’t hurt, but it left an obvious mark there.
Looks like burn. Im not wearing it tightly, 1 finger can easily pass thru.
Did any of you have the same effect?

Think I found out why.
First 2 weeks I use without turning on blood oxygen meter.
Then try it for 1 week and got this mark.
I turned off for 3 days now and it’s healing.
Think my skin is sensitive to the method it use to detect blood oxygen. Cannot use often.