Splitter or Hunter Banelings in HOTS?

Splitter: Best for breaking up frontal walls. More robustness for baneling army. Especially good with rupture mutation.

Hunter: Best for targeting specific units or buildings to kill. Able to do surgical strikes. Especially good with corrosive acid mutation. I suppose this one would be good for frontal assaults when combined with zerglings, as the banelings won't get in the way.

I played the game on hard and brutal, and found that using the Hunter strain works the best.

They "auto" jump to the enemy that is the closest to your Baneling and they require the least micro, leaving you free to micro other units.

I found the splitters to be best VS. clusters of enemies, but all over the Hunters is the best in my opinion.

The different upgrades for the baneling, depens on the mission at hand!