What do you think is better from a tactical standpoint? Putting Healing & Ammo Station in one point and creating a kind of base where you can get both at once and risking that both gets destroyed by one well placed explosive? Or having it seperated and not risking simultaneous destruction but having to go to two spots?
Healing & Ammo Station in one place or seperated
Place them together. Why not? I mean the cooldown is not that insanely high for placing new ones. Usually they don’t get destroyed as soon as you’ve placed them so you will most likely not have a full cooldown to wait.
And if they do get destroyed as soon as you’ve placed them, that usually means you just put it at the wrong location in the first place. 
Two spots ain’t too bad if they’re relatively close to each other so that people going for ammo/ health are capable of getting both without too spending too much time on resupplying.
Defending = Together
Attacking = move around
Btw, i main Nader and i love to find the healing and ammo station together xD
Separated. If you put them together your whole team will gather around them and get wiped out by a grenade or fire.