Our dyno testing has shown the good 'ol smooth tubes and K&N panels work the best, and even better, they are the least expensive alternative.
We tried the K&N box and lost power (probably due to the tight bends in the tubes), and most other systems didn't show any gain over the smooth tube/filter option. The downside I see of the cones is that it ***** hot air under the engine. If anyone has any monitoring software, plug it in and go for a ride while watching the IAT temperature. Our tests shows that it increased noticeably (hot air)without an airbox to minimize the air temps. This solution doesn't look nearly as nice as the others, but it seems to work well.