Wood?

[Bobbytwonames 5,000+ posts]

I use 3/4" pine for all my boxes and walls. Much stronger than 3/4" MDF.

Solid ¾" Pine or just a Pine veneer?

 

[Bobbytwonames 5,000+ posts]

Is the fake birch pretty sturdy?

It's just a Birch veneer. A lot of voids in the layers.