I have an apartment that I will be renting out that is being remodeled. The
kitchen will have a pre-made Lowes post-formed Formica countertop.

However, there is a half-wall divider between the living room and kitchen
and I want put a small countertop on top of the divider. The countertop
will be about 2 feet by 4 feet, and it will have a round end. So, it needs
to be custom made. This countertop will sit on top of the divider wall and
it will overhang past the wall about 12 to 16 inches, and I will put a
couple of bar stools next to it.

Since it will be an overhang that people may lean on, I want to be sure it
is fairly strong.

Typically, I think the way people make laminate countertops is to put two
sheets of 3/4 inch partical board together and install the laminate on top
of that and on the sides. I was thinking of maybe using two pieces of 3/4
inch plywood instead for greater strength. However, I have heard that new
plywood can sometimes "cup" or curve a little as it dries out, so I am
wondering if that may be a problem. Particle board doesn't do this as far
as I know.

So, any thoughts on whether it's okay to use plywood for more strength or
would I be better off using particle board?