Japan has many options when it comes to Infantry, and good upgrades as well, such as Special Forces, Improved Mortars, Foraging, Plentiful Ammunition, and more.. While Commandos certainly have their place in the game, many experienced players can't seem to agree on which in better, Japanese Mortar Infantry or Heavy Airborne. So we thought we would take a moment to profile these two commonly seen regiments, and maybe you can decide for yourself..
 
First, let's take a look at the regimental level, with the most obvious differences being that the Mortar Infantry regiment has [2] Mortar Infantry Units and [1] MG Unit, while the Heavy Airborne regiment has exactly the opposite. The Mortar Infantry regiment costs a little less at $65, and of course these these two regiments are deployed from different HQ's. There are differences between airborne and infantry units as well, but we will cover those in a moment.
 

Mortar Infantry Regiment $65

Heavy Airborne Regiment $75

Japan enjoys the benefit of being the only country capable of earning +$30 from all their HQ's (after military surplus upgrade), so their economy isn't harmed by deploying Airborne HQ's as it would be with other countries. Japan is also the only country that can purchase the Heavy Airborne regiment for $75, all others cost $100 (ground deployed version)

Read More.. [Story Continued]
 

	infantry mortar unit health = 150 defense = 1 speed-max = 2 BlastDamageEffect = 35 MoraleLossEffect = 1
	airborne mortar unit health = 150 defense = 2 speed-max = 2.5 BlastDamageEffect = 35 MoraleLossEffect = 1

	infantry machine gun unit health = 150 defense = 1 speed-max = 2.5 PierceDamageEffect = 12
	airborne machine gun unit health = 150 defense = 2 speed-max = 2.5 PierceDamageEffect = 12

	infantry unit health = 200 defense = 1 recharge-time = 3 Grenade = 20 PierceDamageEffect = 10
	airborne unit health = 200 defense = 2 recharge-time = 2 Grenade = 25 PierceDamageEffect = 12

	infantry commanding officer health = 200 defense = 1 PierceDamageEffect = 10 Grenade = 20
	airborne commanding officer health = 250 defense = 2 PierceDamageEffect = 12 Grenade = 25

zling comments: First of all, as the article says, this is a question mainly for Japan. other countries will be better off with different units, well Germany, especially with Kesselring can also put both mortars and heavy airbornes to pretty good use.
Imho the question boils down to the following: are you facing enemy infantry(SAS, Snipers, Commandos, etc) or early mechs. if facing infantry than the additional mortar troop per regiment is more valuable than the overall increased strength per soldier of the heavy airbornes. however when facing mechs the heavy airbornes shine, being the strongest infantry/airborne regiment available, and that the mortar itself doesn't do that much damage against mechs, as opposed to other infantries.

another thing to note is that mortars are a lot easier to spam, being produced from a 5 unit tent(infantry) as opposed to a 3 unit tent(airborne), so in any type of fast build mortars are superior.