How Much RAM?

An upcoming assignment for class is to design our "Dream Machine". Well, that sounds easy enough, but it has turned out to be quite a challenge. For one thing - I don't have all the time in the world to do this: I actually need a new computer NOW. So, I have a lot of pressure on me to get results fast. I have narrowed my choices to two computers - a MacBook Pro with retina display, and a Windows 8 touch screen. But that is just the beginning decision. The real challenge is to figure out what comes with it; what size should it be; and how much RAM should it have?

Here's a video that demonstrates the differences between 4,8, and 16 gigabyte of RAM. I can't say I understand much of it, but the bottom line for me seems to be that 16 is better than 8. Why? My purpose is to do web development, photo processing, and video editing. Knowing my habits, I like to do everything at once. As I've found out so often, speed of response (and lack thereof) is the thing that drives me nuts. SO - I think I've answered this question.

Take a look for yourself. Here's "A Little Byte of Tech" by Jayztwocents: