Yes. The mamba is not really a cave/hole gun but it does demonstrate what a compressed air gun can achieve.
We have a style of fishing that involves looking for fish in holes in the reef. The only 2 target fish species are wrasse and conger eels. Although I no longer do this I have done a lot of this type of fishing in the past. Wrasse grow to about 10lb and conger eels over 100lb. Wrasse are very akin to snapper and grouper although a bit smaller in terms of maximum size they average 5lb. Conger eels are notorious for their strength and tenacity.
I would only ever use a heavy duty compressed air gun for this type of fishing. Length would be 60 to 90 cm and a double barb head on an 8mm shaft would be my choice.
The main advantage of these guns are; high power at short range (loads of "punch"), easy to handle (you can grab the barrel, use 2 hands, fire with the barrel alongside your head - useful when hunting narrow holes), clean lines (only use 1 or 2 wraps of heavy line). rugged construction (band guns are easily damaged on rocks/reefs, etc, etc.
I could go on, but as far as I am concerned you can't beat an air gun for reefing. In your terms Sarge any band gun (even roller guns) should be equated to a rifle but an air gun is like a pistol grip (no stock) shot gun.
Dave

.