I don't know if you can "see" a difference because I've only stayed at SSR so far. I do know that the value standard rooms are said to be 240 sqft.
The moderate standard rooms at CSR, POR, & POFQ are said to be 314 sqft. That is 54 sqft larger than a value room. I'm not sure how long the rooms are in the values or moderates, but lets say they are 18 feet long. A difference of 54 sqft would mean that the moderate rooms are 3 feet wider compared to a value. Only a slight difference really, but one which you could probably see the difference if you were viewing the rooms in person.
The rooms at CBR are 340 sqft, which is 100 sqft larger than a value room. I would think you could see a definite difference in room size here compared to a value room (if you were viewing the rooms in person).
It's hard to see the difference in a virtual tour though, because you're only viewing the rooms in 2 dimension, so you have no depth perception.