Here's the first dyno plot comparing the K&N panel filters with OEM cats (BLUE) vs K&N + Test pipes (RED).
Gains were decent throughout the powerband. I purcahsed these test pipes off of ebay which includes an extra long defouler
http://cgi.ebay.com/ebaymotors/Nissa...Q5fAccessories
Oddly, the bolts it came with were the wrong size -- otherwise, well worth the cost.
More dynos and commentary to be posted in a few minutes...