HVDs are really good. Mostly because they're always good if they hit - if the enemy tanks on shield, it's heavy kinetic damage, if they lower shields, they have to take the EMP and a decent chunk of damage.
As I understand things, the damage a kinetic weapon deals against armor should be (0.5*[rated shot damage])^2 / (0.5*[rated shot damage] + [current armor rating of hit location]). This would suggest that the medium ballistic kinetic weapons deal the following damage per shot against the listed armor ratings:
Armor 100 300 500 700 900 1100
----------------------------------------------------
HMG 3.33 1.25 0.77 0.56 0.43 0.36
Arbalest 32.1 15.0 9.78 7.25 5.77 4.79
HAC 16.7 7.14 4.55 3.33 2.63 2.17
HVD 79.6 43.2 29.7 22.6 18.2 15.3
HN 5.00 1.92 1.19 0.86 0.68 0.56
which would result in each weapon having the following DPS against the listed armor ratings:
Armor 100 300 500 700 900 1100
----------------------------------------------------
HMG 26.7 10.0 6.15 4.44 3.48 2.86
Arbalest 32.1 15.0 9.78 7.25 5.77 4.79
HAC 35.7 15.3 9.74 7.14 5.64 4.66
HVD 39.8 21.6 14.8 11.3 9.11 7.64
HN 21.1 8.13 5.03 3.64 2.85 2.35
This would suggest that the HVD is actually one of the better medium kinetic ballistic weapons for use against heavy armor.
Unfortunately, armor also has the property that it cannot reduce shot damage below 15% of its hit damage. This means that the damage per shot table is actually:
Armor 100 300 500 700 900 1100
----------------------------------------------------
HMG 3.33 3.00 3.00 3.00 3.00 3.00
Arbalest 32.1 15.0 11.3 11.3 11.3 11.3
HAC 16.7 7.50 7.50 7.50 7.50 7.50
HVD 79.6 43.2 29.7 22.6 20.6 20.6
HN 5.00 3.75 3.75 3.75 3.75 3.75
which means that the DPS table looks like:
Armor 100 300 500 700 900 1100
----------------------------------------------------
HMG 26.7 24.0 24.0 24.0 24.0 24.0
Arbalest 32.1 15.0 11.3 11.3 11.3 11.3
HAC 35.7 16.1 16.1 16.1 16.1 16.1
HVD 39.8 21.6 14.8 11.3 10.3 10.3
HN 21.1 15.8 15.8 15.8 15.8 15.8
Somewhat amusingly, despite armor mechanics notionally favoring high damage-per-shot weapons, Heavy Machine Guns, the medium ballistic kinetic weapons with the
lowest per-shot damage, are actually perhaps the
best medium kinetic weapons to use against heavy armor, while Hypervelocity Drivers, the medium ballistic kinetic weapons with the
highest per-shot damage, are perhaps the
worst medium kinetic weapons to use against heavy armor, with 'heavy armor' being defined as 'mid-range destroyer-grade or heavier armor.'
(Note that when I say 'damage per shot,' I mean per individual bullet, not per firing cycle; HMGs get 4 shots per firing cycle, HACs get 3 shots per firing cycle, and HNs get 15 shots per firing cycle while Arbalests and HVDs get 1 shot per firing cycle.)