Gemfan Hurricane 2" 2008-2 PC Durable Bi-Blade Prop 1.5mm Shaft (4CCW+4CW) - Choose Color

Haven't tried them yet but I'm sure they're solid

Good for smooth flying

These are good for low-grip, smooth flying. Triblades feel better in the air but these will give slightly more flight time.

Efficient

Gives me more control than the higher pitch variety