Is there evidence that suggests users accept/reject pre-fab choices?

Suppose in a scheduling app, I want an adjustable view for what is occurring in the next x days.

There are some things that make intuitive sense (e.g. what's happening today, this week, this month). Perhaps use a dreaded dropdown! OR, one could also give the user complete flexibility: [ Show next ___ days ] and the user fills it in.

Is there evidence (or experiences people of had) that suggests one is generally preferred to the other?