I'm not one to fix something that isn't broken and only occasionally upgrade these drivers if there's a marked improvement, fix or feature. Based on some excitement over at AVSIM for this driver, I went for it and have to say it was well worth it. Very smooth! Reduced micro-stutters and I think, improved AA/shimmering.

I haven't tested this extensively, but so far so good. Haven't tested much in FSX yet, so I don't know if these benefits extend to that sim as well, but haven't noted any negatives. Note that NVidia recently changed the profile name for FSX.exe, it's now 'Microsoft Flight Simulator 10'.