[Imp]

Probably not as much as you might first think, infantry wont be far off & they normally screen the armour.
Long range stuff like the armour & HMG wont be able to start targeting out where you expected but they are vulnerable at short range.
My guess is as its mobile you would move armour up as & when needed to act in a supporting role.
Only big problem is if you have gaps they can slip through undetected.