The Boston for fs2004 certainly does NOT work in fsx without modifications. It may look fine at first but there'll be flickering and tearing on the ground and transparency issues all over. It ran pretty well in fsx sp1 but with sp2 I got like 0.1 fps, something George acknowleged due to the FSSC runways. So, no, it doesn't work, it's just not optimized for fsx, so you'll be better off waiting for the all-new version for fsx.