The water volume is fixed so running a high flowrate shouldnt be a probelm.
If you have a slower flowrate, the chilled water is colder than high flow. However, this chilled water is mixed with the tank water and will lower the tem slightly as the volume of the chilled water is lower.
Having a higher flowrate will have a warmer chilled water but with a larger volume. So you are mixing a larger volume of warmer chilled water to the main tank.
SLOW FLOW
colder temp
lower volume
HIGH FLOW
warmer temp
higher volume
To me, they are the same except when the flow is excessively slow that is when the chiller will detect a much lower temp than the actual temp. This usually affects chillers with water reserviors.