The MG-1's are the lightest of the larger DH style pedals made. They have sealed cartridge bearings. Reviewers seem to think that they have slightly less traction (and therefor are slightly less likely to damage your shins and calves) and are more comfortable to ride. They are however painted (many choices of colors for you OCP/Fred types) and the paint wears off exposing the bare metal underneath rather quickly.
The Ultimate platform pedal though is probably the Shimano PD-MX30 but the price will give you a nosebleed.
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