On Sat, 05 Nov 2005 13:13:09 GMT, Lobster
wrote:

Has anyone tried one of these gizmos?

Yes, they're wonderful.

A little work with a good block plane and an old washing up bowl and you
can make your own. Use polypropylene of the right stiffness and you need
to get a good feather edge on them. Fibreglass or P38 kits often
include something suitable, but without the rounded corners.