On Thu, 9 Jun 2005 23:30:28 -0400, "Carson McAloney"
wrote:

Is Mdf okay for a work bench,

Not on its own. MDF will sag if unsupported, so you'll need to put some
closely-spaced supports beneath it. Alternatively use MDF over ply.

Personally I'd use a replaceable layer of 4mm MDF over two layers of
3/4" plywood.