S2SS on my wrist now at work with $11 M'Keke brown leather band from Amazon. At home I have S3SBSS LTE model. I wear the LTE model for runs and bike rides outdoors without the phone, and it works fantastic for that. I like the Apple "green" sport band, which looks like hi viz green. In fact, the S3 model has become workout watch, and I wear it indoors on treadmills and stairs too. I general wear the S3 the whole day if workouts planned. Wear the S2 the other days.
"Auto Switch" works well, though it does take a few mins after transition for the new watch to find my location for weather, update my calendar, reflect new pulse in HeartWatch Complication and pull calories eaten in MyFitnessPal onto the WatchMyHealth complication.... No issues with Health app tracking continuity between the watches.
I generally airplane mode the one I'm taking off, place on charger to 100%, turn it off and put it in watch box. Lather, rinse, repeat.