120mm seems bit long to me for a macro lens esp for APS-C
"Focal length equivalence" gets a bit funky at macro range, especially if your goal is adequate working distance.
For example, 1:1 macro with a 120mm lens gives a lens-to-subject distance (as opposed to the usual focal-plane-to-subject measure of working distance, which makes little practical sense to me) of 240mm, and that is independent of format size, so at 1:1, this lens is comparable to the same 120mm focal length in 36x24mm format in giving the same working distance.
If instead what you care about is filling the frame with a given small subject, so comparing at equal field size, then 1:1 with this lens on a 24x16mm sensor records a 24x16mm subject field, and to get that same 24x16mm coverage in 36x24mm format, you need greater than 1:1 magnification, 3:2 in fact, and then that same minimum working distance of 240mm requires a 144mm lens.
If instead, the 36x24mm field size of 1:1 on an 36x24mm sensor is small enough, then the 24x16mm format only needs 2:3 magnification, and this 120mm lens then gives a 432mm working distance, as for a 216mm 1:1 lens on 36x24mm format.
However you cut it, 120mm in 24x16mm format is not equivalent to the usual (3/2)*120mm = 180mm in 36x24mm format for close work, even though it is for equivalent FOV with more distant subjects.
Given the interest in 180mm and 200mm macro lenses for 36x24mm format, this seems an attractive focal length for close work in 24x16mm format -- and one of the places where smaller formats with smaller photosites have a nice size advantage. (The stopping down needed for adequate DOF in macro shots allows a smaller format to use a less high f-stop, and so a lower ISO speed for equal shutter speed, which I like because my macro shots often involve the need to freeze a bit of motion, so high-enough shutter speed matters. So many of the touted advantages of larger pixels on a larger sensor are cancelled out in "small world photography".)
