Techgage.com posted an article taking a look at running varying memory densities and frequencies on Core i7 to see if there is any reason to go with a high-end (expensive) memory kit.

Can't decide on the right memory kit to pick up with your brand-new Core i7 PC upon release? This article was designed for you. We aren't comparing brands here, but are rather comparing densities and frequencies against each other to see if there's any point at all in purchasing a higher-end kit. You might just be surprised at our results.

Intel Core i7 - Choosing the Best Memory Kit