I'd never get one for following reasons:
a. No redundant braking. I've had a china **** metal brake lever brake on me before. Good thing I had another lever to use to stop. The lever sheared at the hinge.
b. Brake modulation. With lots of sand on roads and offroad riding, I need a separate lever to modulate the front brakes to prevent skidding while maximizing stopping power. I don't see how a single lever could be adjusted to give me maximum front braking for asphalt, asphalt littered with sand, and off road dirt trails.