OGSSAA
-Very effective at eliminating aliasing
-Can improve scene and texture clarity, especially when used together with a low LoD Bias
-Relatively low performance loss
-OGSSAA works in Mass Effect, Dishonored, and other UE3 games with deferred lighting that are normally incompatible with sampled antialiasing
-Does not alter the size of HUD elements
SGSSAA
-Very effective at eliminating aliasing, but not quite as effective as OGSSAA
-Can improve scene and texture clarity, especially when used together with a low LoD Bias
-High performance loss
-SGSSAA also works in games that are normally incompatible with sampled antialiasing
-Does not alter the size of HUD elements
-Seems to retain a slightly sharper image than OGSSAA, in return for the higher performance cost
Downsampling
-A downsample of 1440p (2X compared to 1080p) eliminates most jaggies, and is similar to 2X supersampling
-A downsample of 2160p (4X compared to 1080p) eliminates all jaggies, and is similar to 4X supersampling (albeit with a higher FPS cost)
-The most effective option for increasing scene clarity, especially in DX9 games
-Very high performance loss
-Improves AO quality
-Downsampling also works in games that are normally incompatible with sampled antialiasing, but is even compatible with games that do not support any hardware AA
-Alters the size of some HUD elements in some games