I have barely been on MY Grady.. lol
Ya know, I went through the same issue....it is all about the fishing space. I came really close to getting a C-Dory before getting this boat. I loved the idea of the cabin.. an a/c.. a place for the wife to relax in comfort.. but the fishing area, specifically "A".. was sooooo small (I did not see they had one model with a lot more room heh...), and, yea.. they are slow.... bumpy...not made for the Gulf like I want, really.
I do not think the differences you will find on these models will make a difference. To ME... what makes a difference is how you stow things, how much you bring, and such. For instance, I have one of those friends that drinks diet 7-up like it is going out of style. He brings along 3-ltr bottles and he just about pouts like a 2yr old when he cannot bring his 300000 qt ice chest to stow it all in.. heh. Love the guy like a brother, but that bugger pretty much eats up the back space.
For me, I do not care if my drinks mingle with the fish in the fish box. I have a large ice box on the transom, I can put a few cold drinks into the fridge and they can stay cold a while sitting there, if I took them out of the ice box before leaving the ice box in the truck, I can throw a few in ice next to the sink, and, hell.. I can throw more into the fish box if it is that big a deal... should not be... not staying out 24 hours and even so.... I can hold PLENTY of ice for 24 hours and drinks. So...will be keeping his box off the deck/boat.
If you have 4 grown people fishing, the lines are your worries.. we took the boat for a 15 minute spin and we had .. 4 adults, 2 younger adults, 2 kids.. and one of the adults was pretty darn large. All we did was drive around for 15 minutes and we were fine.
Fishing would have been a pain, but I limit that to a couple adults and a couple kids and you have more than enough room.
In a nut shell, I would not worry about it. The only way you get more room back there is pay a heck of a lot more. If the boat runs good etc.. you'll adapt by how you organize it.
R