Have had the watch for a week and am a first time adopter. Love the tech particularly regarding health stats. Disappointed that there is no ecg.
As I have a work phone there is also an issue with being able to get an e sim on business phones.. currently not supported by Telstra.
I have the 44mm gps and sim version and this fits my wrist perfectly. Resolution for photos is also really good

The new bigger screen is the main reason that I decided to upgrade to the series 4 and I am glad I did it is amazing and then there are also the added health features like ECG and the heart rate monitor (although this was on my last Apple Watch) when you think about it all of the health tech in it makes it a worth while product to have if it could potentially save my life then it is worth the $650 to me.