I have 50mm and 180mm, i think i should get either 110 or 90, many recommend me to go with 110, but i am very very happy with that 50 and 180, you can't go wrong with 150mm either, but i feel that 180 for me is better than 150 but i can't tell until i can use one, i may prefer 150mm for Hasselblad 6x6 format which i have and happy.