I have seen a lot of reviews that show that the primes are equal or sharper than the z, but they don't compare things like AF speed which would be the thing to get me over the hump. I have the 50 and 85 just now, and am considering the 24 and 35 or the 24-70 f/2.8.
Comments
The only obvious thing for me is, what do I need in terms of light conditions. With the Z lenses I can shoot with 1/10 of a second without tripod (IBIS) unbelievable, so with the 50mm f/1.8S almost in darkness. The 24-70mm f/4S is very handy and compact for a lot of situations, making it the most used lens for me (which was the 24-70mm f/2.8G anyway).
My perception has changed a lot with the Z series.
Still waiting for the 70-200mm f/2.8S and the pancakes.