I can't speak to the Z170 series from personal experience as we're still giving the channel another two weeks to clear out all the old stepping boards. But with the Z97 series, the Krait was an absolute bomb. The MSI and Gigabyte who have the same model (Gaming 5) were way better.
The ranking is based on setting the board which recorded the highest combined fps in the gaming tests at 100% and ranking the others by fps as a % of the fastest one.
MoBo % of Leader
MSI Z97 Gaming 9 - 100.00%
MSI Z97 Gaming 5 - 99.86%
MSI Z97A Gaming 6 - 98.96%
Asus Z97 TUF Sabranco - 96.13%
Gigabyte Z97X Gaming 5 - 95.00%
Gigabyte Z97X SOC Force - 94.95%
Asus Z97 Maximus VII Hero - 93.67%
Asus Z97 Maximus VII Formula - 93.58%
Asus Z97 Maximus VII Gene - 91.69%
Asus Z97-A - 89.57%
MSI Z97 Mpower MAX AC - 88.20%
MSI Z97S Krait SLI - 71.01%
Now looking at Z170 series we are not seeing those huge differences ... so far. pretty much all the reviews I have read on Z170 have the boards performing within 1 or 2% of one another. But the RoG boards are still waaaay overpriced.... hard to argue towards getting the $300 board over the $150 and hard to argue for a RoG board when the competition is $50 - $90 cheaper with similar or better performance, componentry and features.
I'd echo the Gigabyte Z170 Gaming 5 recommendation from above or MSI Z170 M3 / M5
I can't get behind the Asus Z170 pro tho ....
http://www.newegg.com/Product/Product.aspx?Item=N82E16813132567
Not with 1 in 4 people who own it giving it a very unflattering 1 egg rating on newegg.