Like I said I only have 2 years experience with using this setup in my classroom, but I could not imagine it any other way. May students know the routine of the stations. They know how much time they have. They know they are held accountable.
And most importantly I feel they are having fun...they love math and I truly don't hear any complaints.
I use this time so children can see how much time is left. It turns to yellow when they have a minute left and then red when done.