whats better for flag settings 128 or 256 ? and why ?

[Billy the Bit Miner]

running GUI miner i had some one say in one of my last post i should have my flag set to 256. whats better for flag settings 128 or 256 ? and why ? and no i dont care about the rigs desktop performance.
using a amd radeon hd 7770 1gb gddr5 oc to 1050 factory setting
i have it over clocked and getting some nice boost with my current flags btw

[Behemot]

Well, just try both for a while and pick up the beter one?

[UltraJake]

Some people recommend 128 and some people recommend 256. It shouldn't make a huge difference, but I tend to use 256.