The DMR V12 is probably the best flat pedal available (2nd only to the Magnesium V12!). It is not a cloned pedal but a 100% exclusive DMR design, and because it is so good it has already become a classic, and the pedal of choice for many people.

Oversized fully chromed Cro-mo axle
Tough 1 pc body
Runs on a sealed cartridge bearings & a plain bearing, which can take very high loads
Double sealing at the crank arm end (external splash guard & internal double lip seal)
Better sealing combined with fully chromed axle means that the pedals will run a lot smoother for a lot longer
Replaceable screw in studs
Fully rebuildable - all spares are available
Stocked in 9/16 thread (MTB)