My two cents on this system comparison.
You should weigh the pros and cons adn also perform an energy simulation to see if VRF actually saves you anything. i large applications like your project the chiller can be better and you also can recover heat and use for perimeter heat if the core needs cooling etc.
VRF systems offer heat recovery options as well. Unfortunately, my office only uses Daikin so I'm unfamiliar with what the other manufacturers offer in this area.
As Drazen pointed out, you marry your client to a manufacturer. In addition you have condensate lines throughout the building, refrigerant, and have filters to clean in each zone or hallway.
You'll need condensate drain piping to each evaporator, AHU, fan coil in both chilled water systems and VRF.
It really depends, there is no black and white when it comes to any HVAC technology. If your client already has room for AHU etc., a chiller system is more likely. i currently work on a small project where there is no AHU space and i would have to create one (and reduce other spaces), for that VRF may be the lesser evil.
Both options allow you a number of options for evaporators. I have not seen a large difference in cabinet size for evaporators between the two systems. They'll both just essentially be a small fan, coil, filter, control box, etc.
One of the mechanical contractors that are also engineering compnay has made a comment as why not go with a VRF (Variable Refrigenrant Volume) system.
This is surprising to me. In my experience, I still find contractor knowledge of VRF systems to be very limited.
The primary advantages to a VRF systems are as follows.:
-Less rigging, a lot of condensing units weight less than 1000 lbs
-No boiler plant is required, like Herr said, this is dependent
-Refrigerant piping is smaller than chilled water piping
-Less landmarks concerns versus a chiller
-Less structural concerns versus chiller system.
The disadvantages are:
-Installation & Maintenance: Possible contractors may
not be familiar with system.
-Refrigerant piping run lengths are limited
-Potential for refrigerant leaks.
-Large quantities of refrigerant within the building.
That's the short list of advantages. I could tell you a bit more if I knew if it was a water or air cooled chiller.