Advice on Star Trek Models...

Ok need advice. I've been grabbing eaglemoss model/diecast. Grabbing Federation first. I made the mistake of getting larger xl model for first NCC1701. NCC1701b is otw, but should I get the xl ds9 model (around 8") or normal (around 4"). I have more display area to put those 2 and the other alien ships. 



Autographed Freddie Freeman ball for scale.

So 4" or "8?