If you believe marketing, (which I don't) the best one is the "One Blade."
In my opinion, the biggest limiting factor for single edge razors is the lack of blade variety. They all lock you into either a single blade choice, or a single brand of blades.
Schick injector, GEM single edge, Feather single edge, or the four different choices from the Feather Artist Club line.
I wouldn't call it a "consensus," but in my opinion the best single edge razor is the G.E. Jones Shake Sharp. These were produced in two varieties, the earlier one, with the bakelite handle is the more aggressive of the two. The all metal second generation version is more mild. These unique SE razors take DE blades, and for that reason, offer more variety in the shaves that can be coaxed from them.
Alas, they are not very common. However, anyone willing to pay up to $100 can obtain one within a few months off of the U.S. eBay site. They used to be much cheaper and easier to find before they became popular. Maybe someone will make a modern version one of these days.