Aquatica port preference

HI I'm looking at a used aquatica set up and I'm wondering what the biggest differences are between the 8" and the 9.25" dome port is?

The 230mm 9.25 inch port is optical glass and runs around $1760.00 new in the US. The 200mm 8" comes in acrylic with acrylic at  around $550.00 new. 

Bigger is better for split shots, sharp corners with wide rectilinear lenses and more.