Greetings all,
I recently purchased my 2001 Boxster S (last week Wednesday), and could not wait to start playing around with it on my dynamometer.  I am an engineer, tuner and enthusiast, and have designed parts for NSXs, S2000s, and even factory supported FWD drag race teams.  My race program involved many secured world records...but I digress.
Since I own my own Dynapack Chassis dynamometer, and noticed some confusion in this board (yes, I have lurked for a while) in regard to if de-snorking produces any other benefit above an enhance intake roar, I took it upon my self to perform the following test.  Each run was repeated to ensure credibility.  
My bone stock S: red line
De-snorked (15 minuets later): violet line
 
A 5 WHP GAIN!!!!  In addition, almost 3 ft/lbs of torque
Finally some proof, and feel free to share this with our peer members.  This is the most cost effective gain I have seen in a while!
On the dyno:
 
Left over "organ":
 
No tyre interface to introduce, variables like other cheaper intertia dynos. More data to come, as I try some interesting technology on the S...