I did a search and had a hard time coming up with specfics. Both blowers can make awesome power from what I have seen/read. Myself I am leaning towards the 3.6 KB, the LC option just has too many positives to pass up. But I have to admit the Whipple looks cooler (IMO) and the 4.0 is on some pretty awesoome builds on this site. Good luck, look forward to reading about your build.
I just installed the 2.9 Whipple on my 11. Fits under stock hood and didn't have to bias or bang anything. Also, the Ford Racing tune is compatible with cats and emissions.
Give me a call and I'd be happy to discuss my findings and experiences with both products as a customer of Whipple and Kenne Bell before I became a dealer for Kenne Bell.