In fact ive used SweetFX for both COD and ROF, in ROF you dont really need the SMAA because it already has 8XFSAA and 8XAF...but its useful for adding a little sharpening to the textures, making them look even more brilliant!
In COD SweetFX helps a bit in the cockpit and your own aircraft but get any further away and it doesn't really help, because COD only has 2x FSAA, COD's real problem is in the LOD at medium and far distance, where as ROF doesn't have LOD's it renders the full high detail LOD at any distance, it also keeps the markings.
One of the things im really looking forward to in BOS is seeing a flight of 109's with proper FSAA and AF.