Does anyone know how to tell if Deardorff 8x10 front swing plates are bent?

I have one to evaluate, and the front standard is much more rigid with the swing locks positioned to the rear of the arcs, but the plates don't visibly appear to be bent. So I'm wondering if there is a slight bend or if I'm just seeing flex of the plate.

This is normal. I always keep the lock knobs at the back. The design is always going to allow a bit of fex if you lock the knobs at the front. Just keep the knobs positioned where they minimise the flexing.