Are you asking what you need to know?
Is it worth the cost? What size do you need? How often are you going to replace the water bottle? Do you drink enough to get a monthly contract with a water delivery service?
Do you need a cooler, or just a room temperature dispenser? If you get a cooler, do you want a hot water button as well?
Will there be kids using it? (See above hot water question, though they have a basic safety feature). Will they be spilling water on a floor or carpet?