If money were no object, I'd go with the bench dog cast iron top and
router lift plate. It's made to be a table saw wing (which is how I
have it installed), but you can also get an end-cap for it to make a
dedicated router table top. It's not cheap.

I've heard also that harbor freight has a similar cast iron router
table top for something like $60. IIRC, it won't take a standard size
router table insert plate. It has only a hole for the router bit to
pass through. You have to attach the router directly to the table.
That may not be a big deal though if you have a plunge router with a
router raiser attachment.

brian