I've done some preliminary comparisons with different uGrids values and, so far, I'm noticing that the game seems to run pretty stable with higher numbers (7, 9, 11, 13, 15). I know in previous Bethesda games, if uGrids were set too high, not only would the games tend to crash, but it would also affect game play and quest lines in a negative manner.

That being said, has there been any word from the development team as to what they would consider to be the maximum "safe" uGrid value to use in order to get the best possible visual benefits while also protecting against gameplay anomalies from occurring?

Right now I'm doing my initial play through with uGrids set to 9, and in terms of stability, things seem flawless. I've actually been able to boot into the game with uGrids set to 21 before it ultimately winds up freezing shortly thereafter. Of course, I would never consider playing the game with uGrids set to such a high number - that was strictly for testing purposes.

With the game already having a better draw distance than the previous titles the question becomes is raising Ugrids even worth the fuss or time. Considering that a developer may never respond to the question, I'd say for most players should just not bother altering ugrids until they have at least finished the game.

Anyone altering uGrids should be careful because it is known that reverting back to a save that has a different uGrid parameter will cause the game to crash.

I don't believe they changed static amount of preallocated memory to dynamic even after moving to x64. So better to backup saves and do lot of long tests.

This post from Skyrim explains how to revert, still, is best to make a test character OR make a copy of a latest save and backup all your save files in a 7zip file or another folder.

As a note, I have been running at 9 for 24 hours of gameplay now with no crashes.

http://www.gamesas.com/topic/1274926-ugridstoload-skyrimini-comparisons-and-explanation-default-57911/

Very nice!