Throttle bodies have standalone management to control them, just like a T4 eqquiped Escort Cossie, for example Autronic is management. This is why they are so expensive. However you can map them to the finest detail, you save petrol when you are trying to be conservative, because fueling is ecu controlled, etc, so whilst they are an expensive outlay, they are cheaper over a longer period. Also once setup, thats it.

Carbs or bike carbs are mechanically setup, and will require tuning every so often. There is only an ignition ecu, so fuel isnt controlled by the ecu but by carb (4 of them in your case)

Going turbo is cheaper than going throttle bodies and will net you **/*** hp and torque. Throttle bodies will net you 30hp, hardly any torque, and there is instant response. Turbo will give you lag depending on what turbocharger is used, however if you use a small one you wont notice it much.

Hope that helps