First off, what is best for a specific person, I cannot say. Speaking in generalities, Water Fasting is best for those already in excellent shape. Juice fasting (or the MC) provides nutritional support, and slows the detox down, making the cleansing reaction more tolerable. Personally, this allows me to fast longer and more effectively. It also allows me to function. The hunger is usually gone between Day 4-6, and then it is fairly easy.
Do all the reading you can, and make the decision you are most comfortable with for yourself. And allow yourself to make adjustments that feel right. I don't mean changing the protocol of the MC, for instance; but many change from juice fasting to the MC, or from juice to the MC. Any step you make toward improving your health is great one!