I must say the brake works much, much better than expected. I got it set up just perfectly, and it feels I don't even need a second brake.
You are correct, provided you are happy with only 30% of the stopping power of the bicycle. I, must ask this question, though...
Why do you not want a second brake?
Bottom line is: I say nice bike. Ride it safely.
Both brakes are required to satisfy this mandate, in my opinion.
I, sometimes, allow form to push function to the side, but not when safety is involved.