Excellent extinguisher for most types of fires, and a very good extinguisher for novice users.
Dry Powder is ABE Rated and the extinguishers themselves are cheap to purchase and lightweight to operate, as well as achieving vey good Fire Kill ratings compared to most other extinguishers because of a very quick knockdown effect.
The only downside to Dry Powder is that it is very messy, and the powder (typically Ammonium Phosphate) is mildly corrosive, affecting printed circuitry such as electronic equipment particularly. ABE Dry Powder must never be used in the vicinity of aircraft, as it would be necessary to pull apart the affected area rivet by rivet, piece by piece in order to clean it and prevent corrosion