Okay, this new damage 2.0 thing has got me VERY confused.
The greatest thing I am confused about is the grineer. When this system was all new and there was only 5 categories of enemies (Armor, Flesh, Sheilds, Infested, Robotic), I remember when corrosive was the choice for all armored grineer. But now, I'm having some doubts.
How, for instance, do you kill a Ferrite armored grineer with radiation or an Alloy armored one with corrosive? I know that corrosive reduces armor and radiation is essentially a pocket Chaos, but they don't scale well when you need to kill one or the other when you only have one damage type or the other.
On the other hand, Viral damage seems to punch through. Not only does it affect all grineer humanoids (All of them are cloned flesh), but it also has the benifit of reducing max HP to about 50%. Corrosive, while the effect is permanent while viral and radiation lasts a limited time, still is killing the enemy quicker. In fact, health damage has been much more effective now that armor is less effective.
On Lieutenant Lech Kril, with a modded Bronco (220% damage with 180% multishot) Equipped with Corrosive damage, it took an avg. of about 18-20 shots to get a kill during 5 runs. With Radiation, it took 12-18 shots. With Viral, 14-17.
(NOTE: Of course, these vary with proc chance and crit chance, but I needed a guarenteed multishot percentage in order to get results. I would have used Brokk, if I had it.)
In order to get clearer results, however, I would need to use a primary weapon. This is due to the fact that the elements scale much better (clear 90% dmg. all over instead of 60% for freeze mods on pistols and melees.)
But, based on these results, Corrosive took the longest to kill while Radiation generally took the shortest to kill, with Viral being the in-betweener.
I may have to test more, but that's just how it is.
In conclusion, this new system is the most confusing I've ever seen. No two damage types are simmilar, and some may do more than others. But, in a way, most of them ARE specialized, and it is based on playstyle.
But now, I'm taking viral along with corrosive when I'm out to slaughter some Grineer.