Outer Limits 4x4 Board

I am fitting a set next week so I will let you know.

One advantage of external over internal beadlocks that comes to mind is in regard to protection from trail nasties.
There are always bits of log/stick and rock that try to wedge themselves between the tyre bead and the rim cuasing slow leaks.
With my external ring type locks this was not a problem, although the rings did get quite trashed on occasion.

Good point Matt, externals also strengthen the outside of the rim so you dont end up bending it when you smack rocks.