Fan guns are generally external mix guns, but they have one distinct advantage that makes them the Swiss army knife of snowmaking: coverage. Their extended hang time, the time snow spends forming in the air before landing, produces bigger, drier flakes. They also launch snow substantially further than standard snow guns. On top of that, newer models offer automatic pivoting controlled remotely, allowing a single unit to cover exponentially more terrain in one night.
A common myth is that fan guns don't use compressed air. In reality, compressed air is essential for nucleation, and compressors are clearly visible on many models. The exception is the TT10, which has the compressor built directly into the fan rotor.

TT10 Snow Gun

SMI Polecat

Demaclenko Evo 3.0

HKD Diablo

T40

MND Peak +

Areco Super Snow