I just read a review on MotoUSA and they favored the Suzuki GSX S1000F over the NK1. This article may have already been posted (my apologies if this a re-post) but I found it to be a very good review and evaluation of both bikes.
9http://www.motorcycle-usa.com/2016/02/article/2016-suzuki-gsx-s1000f-vs-kawasaki-ninja-1000-comparison-review/
It was close, but a nod was given to the Suzuki.
I have to say that the NK1 is a great bike and I would probably still choose it over the Suzuki. The GSX is a bit closer to a pure sport bike, which I really like but I still like our bike better for a number of reasons.
The NK1 still has plenty of performance and with the Ivan re-flash probably nearly as much HP. In the review, they said the Suzuki had a twitchy throttle in the low range, which I really don't like because it takes away from everyday riding. I have the spark black 2015 NK1 and it looks better than either the blue or red version of Suzuki and I am not a fan of the hawk beak front end in the Suzuki. Not to mention, if you are into touring the NK1 is more capable with its multiple pannier options- not sure what options are available in the Suzuki.
You can not go wrong with either bike, but the NK1 is still I think an exceptionally good package vs. the competition- I am very happy with my choice.