SpO2 is probably what it would take to get me to replace my current Series 4. Everything shown today (what little there was) was a "nice to have", making it a "

SpO2 is probably what it would take to get me to replace my current Series 4. Everything shown today (what little there was) was a "nice to have", making it a "if you skipped an upgrade cycle or two" device to me. (For contrast, Series 3->Series 4 was a big enough jump to buy a new watch a year later.) That ceramic case is tempting, though.