Iirc, its AoE is smallish, and itd dmg actually inferior to, for example, Tellers.
Considering the high muni cost compared to mines, the essentially useless "i blow it when i want to, even though automatic detonation works just as well", it doesnt really have by function distinct or superior to mines except demolishion of unoccupied buildings.
This isn't really true. The AOE and damage on the demolition charge is high enough that you generally guarantee a squad kill especially as you can wait for any stragglers to come over to it, while mines will usually not kill a full squad except in chokepoints that make units clump up. I feel the triple cost compared to mines is overall justified by the ability to choose when to detonate.
If anything they're relatively bad against buildings, squads inside buildings nearly always seem to stay alive with 1 model from the explosions.