I have both and like them both...
+1. Here's my lengthy .02 cents!
I bought my 08 first and bought my 06 ZX14 at the end of the 08 riding season. Why buy the 14 you ask, well because i can and it was a sweet deal of $5K with 3k on the odometer.
The first thing that grabbed me was the difference in seating. What i like about my 14 is that the seating position is much lower then the busa which results to less pressure on the wrist. Some Busa riders complain about the seating position but they sell risers to fix that.
The weight distribution on the 14 is much better then the Busa, by specs the bikes weigh about the same but the 14 feels much lighter then the Busa while riding and throwing it back and forth while riding in the twisties. The Busa has a larger fuel tank by half a gallon.
Braking for both i have no problems with, i'm running braided hoses on both bikes with stock rotors and pads. I owned a ZX7 for about 3 months before buying the Busa and 14 but 3 different bikes in comparison. Now from what i hear about the gen2 busa the braking has improved compared to the gen1. Don't know because i've never ridden a gen1.
I like the styling of both and have since swapped out the Foreman grills for solid panels on the 14. Wasn't a big fan of the gen2 tail at first but has grown on me since. Both of my bikes are lowered, stretched and blinged out.
Aftermarket parts for the 14 are hard to find and the maintenance cost for me run the same and i tend to ride them both hard. i deal with the same mechanic and i have never had any tranny or engine issues like people have been claiming on my 14. I wouldn't go as far as saying the Busa has a bullet proof engine/tranny but a combination that has been proven to be dependable over time. Service them regularly and the setup will last you the entire time you own it.
Performance wise i have them set up the about the same. I have the same exhaust, run PC3 on both bikes and dynoed. The Busa shifts smoother and seems to have a better throttle response then the 14 but corners worse. I can lay the 14 over easier for some reason in the few twisties i've rode on. My wife and i do alot of riding together and we always open them up on a nice stretch of highway and because she's lighter then me she always beats me regardless of which bike i'm on. The 14 has a nice midrange powerband but not enough to to pull away from the Busa at the top end. Never had either of them down the track and really don't care to, track racing is about like NASCAR.....boring IMO.
Cult following the Busa has the 14 beat by far and i'm on the 14 forums as well. Alot of debate of which is faster or a better built bike on both forums, there are alot of facts and alot of BS but in the end its all in rider preference.
Will i ride with Busas on my 14...yes i will. Have i out raced other Busas on my 14...yes i have. Do i get challenged by other 14s when i'm on the Busa not really because here in Dallas, i see alot of Concourses, i just don't see many 14s out. I have more liter and a few 750 bikes wanting to run me when i'm on either bike. Liter bikes give me a good run. Am i mad because i can't beat my wife....YES I AM. I would rather lose to her then some douche canoe on the street! I'm now looking to buy a Zuki liter bike.....why because those damn liter bikes are wicked fast and the wifey says i can! What in hell am i gonna do with 3 bikes, don't but it'll be fun to trying to figure out what bike to ride when its not raining.
I would suggest you ride both bikes and see what you like. IMO both bikes are about the same and yourself will have likes and dislikes after you ride them. In the end its gonna be your preference and how much you want to spend. Busas have a following which in general tends to drive the cost of the bike up but with the economy the way it is Busas and 14s are getting cheaper. If you search the net you can find some nice bikes out there.
I hope my .02 cents helps you. I just wanted to share with you since i own 1 of each.
You said, Um..."Ninja" 
. Who cares what anyone else says, it's YOUR MONEY !! Both bikes are so close, I doubt you could use all the capability of either, so which is faster or whatever is a mute point. I still go with, WHICH ONE DO YOU LIKE 
