We're not cryptography experts, so we can't verify all of the encryption claims providers make. Instead, we focus on the features provided. Bonus features like ad blocking, firewalls, and kill switches that disconnect you from the web if your VPN connection drops, go a long way toward keeping you safe. We also prefer providers that support OpenVPN, since it's a standard that's known for its speed and reliability. It's also, as the name implies, open source, meaning it benefits from many developers' eyes looking for potential problems.
They even offer the most generous simultaneous connection count, with six simultaneous connections through their network, where everyone else offers five or fewer. NordVPN's network isn't as large as some of their competitors, so if you're trying to obfuscate your tracks, you might want a company with more servers. Otherwise, this company is clearly providing a winning offering.