NGFW Competition

I have not seen the 2017 Gartner NGFW report, and not even sure if its out yet.  But I know that my thoughts on the best NGFW firewall lines up with what Gartner appears to think.  Personally, I base my opinion on my experiences and my own knowledge of firewalls.  I've spent a long time working with firewalls, and Palo Alto and Check Point are the best on the market (IMHO).
One more thought about security.  Please don't expect that your company is secure because you bought a firewall at a great price.  Threat protection, Anti-Virus, Anti-Malware, etc.  These come at a price.  Don't think your company is secure because you have an ASA (without FirePower) or a cheap firewall.  If you are on the security team or the Director/Manager, security should always be in the forefront of your mind.   Think about the companies you hear about in the news.  You may not make the news, but you may have a "resume generating event" if you have not properly prepared your company in the security world.
From 2016: