If your phone supports e-SIM, it is advisable that you consider enabling it.
ADVANTAGES
1. If your phone gets stolen, the thief cannot disable network connectivity by removing the SIM. You have a chance to locate it and even get it back.
2. You can use the SIM card for the same number on your LTE supported smartwatch, if you have one.
DISADVANTAGES
1. You can't change your device easily. Physical SIM card has the advantage of simply removing it from one device and using it on another. You can't do that with e-SIM.
2. If you happen to delete the e-SIM profile on your device by mistake (more likely than losing a physical SIM), you'll have to visit the Store to have it reinstated, just like with physical SIM.
I never considered buying a smartwatch because the usual features that they advertise - heath tracking, is a gimmick. But now that i have one, with support for calls and GPS, I'm finding it useful.
But we should use this lte watch for Calls whenever it is required like Jogging/Morning walk, Swimming time or where we don't want to carry our Mobile..Otherwise on "Aeroplane" mode because it drains Battery faster then Bluetooth Variant..This is only the Cons i got from my Friend using "Samsung Watch3"
Yes, the ability to make/ receive calls, notifications, navigation without the phone is very useful for the scenarios you mentioned. Carrying the phone when running is a headache. So LTE supported watch extends the functionality by quite a multiple.
I've had all versions for LTE watch from galaxy watch 46mm till jow (watch 4) never used lte feature! Note Bluetooth does all the job for answering calls etc, Samsung supports wifi call as well in Bluetooth since it's now running android over tizen UI you don't need to specifically buy LTE watch just runs out of battery quickly ! Only benefit is when when you're travelling and your phone runs out of battery!
