Developers ask this on every mid-rise project, and the honest answer is that it depends on two variables: height and duration.
The height variable
A mobile crane loses capacity fast with height and radius. Past six or seven floors on a constrained urban plot, you are hiring a much larger mobile than the load justifies, purely to reach.
The duration variable
A tower crane carries erection, foundation, dismantling and a monthly cost. Spread over four months it looks expensive; over eighteen it usually wins comfortably against daily mobile hire plus standing time.
The footprint variable nobody prices
A mobile crane on outriggers occupies working area every day it is on site. On a tight plot that lost space has a real cost in materials handling and sequencing, and it rarely appears in the comparison.