The CP was the first mod I did for my car. There is technically not a "best" charge pipe. Evolution Racewerkes, STETT, and ETS are good charge pipes that a lot of members here have been running. All with no complaints that I know of. What's good about your N55 is all the parts are so much cheaper than the N54s. I paid about $520 for my CP and BOV, but your charge pipe is like $200
. But it sucks you can't have a BOV...below are links to all 3 charge pipes I mentioned above, you just need to make the decision after reading on the details of each and see which one you like more
I have the evolution racewerkes one on my n54 and have 0 complaints about it. Except for the fact they didn't send me a coupler that connects to the intercooler piping - I had to use the stock ribbed one.