I have D2 coilovers and yes they are harsh on uneven roads.
But they handle great and feel very confident when attacking a bend or roundabout.
If you are looking for comfort steer clear of them,and if you are ready to compromise then go for them.
The older top mounts have a habit of knocking with time or if driven too long on uneven roads,the new designed top mounts have a bush in them,much better.
As for leaking,i havent heard or seen any leak so far,most of friends have D2,and we havent see any leak so far!