The 120mm macro is the best lens in the S range...or at least that I have used. I think if you have the 30-90, the 120 is probably a better choice. It does very well for landscapes, since it is perfectly sharp at basically all distances and apertures, and the focal length gives you a bit of reach, but not so much as to lose all your context. In addition, it is a 1:2 macro lens, is faster than your 30-90, and makes a great portrait lens. For me, anyway, it would be a no-brainer over the 24mm, which is an extreme wide angle that would see very little use (for me...again, your photography might be different, but since you already have the 30mm, that is fairly wide on the S...if you need wider it would be easier to stitch than it would be replicate the characteristics of the 120 macro (DOF, close focus, reach at full resolution etc).