If given the choice between 2 of the same focal length but different f/x value, is it generally (not considering the build and image quality of the individual ) better to choose the larger as this will give you more flexibility in terms of size?
example: 50mm f/1.8 and 50mm f/1.2
70 - 200mm f/4 and 70 - 200mm f/2.8
If so, then why do people choose the smaller instead? Larger = higher cost?