The Sonnar is often overlooked because is the standard lens that almost everyone buy with an Hasselblad.
But this do not means that it is not a great performer.
Quite the opposite, indeed!
Designing a normal lens is easy, even without resorting at rare earths or others magic ingredients.
And this Zeiss does not make an exception.
It is sharp all the way, at all the apertures, and with the great and well known Zeiss contrast and colors.
The only thing that someone may find unappealing (but I think only on the old models) is the lock that tie together apertures and shutter speeds (the lens has a leaf shutter) linking them to a specific EV value.
For me, instead, this is a plus, because once the exposure has been decided one can fiddle around with aperture and speeds values without the constant necessity of recalibrate.
Performance-wise if it is not a legend like some of its siblings of the Hasselblad lineup surely it is a great great lens.
Speaking of Hasselblad legends a valid alternative, but costly, is the Planar 100mm f/3,5.
Anyway with any of them you will be plenty happy.
Rating: on film