I apologize for my extreme limited knowledge but I though HW3 only matters if you have FSD and if you dont but decide to upgrade during delivery or way down the road, they will replace to HW3 with FSD anyway
True, but if you want to upgrade eventually and already have the HW3 in your car, it can be done as a software update, and you wont need to go to the service center.
At least that's my understanding.