Devils advocate here, MDF laminate both sides, makes a really nice finished
product and frankly you'll be amazed at how rigid it will turn out. I made a
similar work center for a pals college student. I used 1" mdf bisquited on
an inch of red oak laminated over the oak on both sides an ran a 1/2"
roundover for a bullnose finish. The kneehole had a 40" span and I could
jump up and down on the thing with my 300# self and it deflect about 1/8".
No sag no way...

Knothead