WP Security Ninja has been around for over 7 years.
This means that they have had a lot of experience dealing with tweaking their firewall to identify security threats.
The creators of the plugin have helped over 20.000 websites with their security since 2011.
Additionally, Security Ninja scores excellent reviews on the web, with for example 5 stars on the official WordPress website.
Now, this is not always proof that the product is actually great, but it gives you an indication.
What I find important when installing a plugin is that it does what is says.
Questions before installing any plugin should be:
- Are the features compatible with your theme?
- Is it safe to use?
- Does it slow down your website?
- Will the plugin make changes to your website?
- Is it compatible with other plugins?
From what I have experienced with Security Ninja, these questions can all be answered in a positive fashion.
I am always the most worried about the addons affecting my website speed.
Luckily, this excellent WordPress security scanner did not show any changes in my speed tests.
I have performed the tests on differents websites, just to be sure.