I purchased 2 yubikey devices in May I purchased 2 yubikey devices in May, paid for express delivery, and still waiting for the devices to arrive at mine. I have tried to contact them via tweeter and emails but no headway so far

Solid security keys I've owned a variety of YubiKeys since 2014, and I've always been very happy with them, I've only had to replace them either because I lost them or because I wanted some newer features, like USB-C or NFC. They seem to be the gold standard for security keys for a reason.

Stress-free 2FA I've got two Yubico Security Key NFC keys and the build quality is excellent. They've been pain-free to set up on all my devices and with all of the online accounts that supports them. It might be worthwhile checking which services support specific Yubico keys before buying them so you won't be disappointed, since it varies depending on the model you buy. These keys have been great for my personal use and the companion app, YubiKey Manager, is nice and simple to use.

U2F Keys from Yubico I think having this type of security (U2F Key) and replacing other methods is just excellent. Combined with a password manager like Dashlane for example is just top notch and definitely safe from attacks. It's an open authentication standard that enables internet users to securely access any number of online services with one single security key instantly and with no drivers or client software needed. They come in many sizes fit to the users needs, obviously make sure to have a few spare.

Non Existent Customer Service - Also Just Plain Rude Shockingly bad, full-friction customer journey. Customer Service is non-existent for all practical purposes including initial purchase. I wanted to spend 15 minutes buying these security keys - I'm at the end of day 2 now and still haven't made the freaking purchase due to non-existent help from Yubico and their so-called resellers in the UK. The resellers don't actually sell anything, they refer you on to someone else. If you want to get a freaking headache then please go ahead and start your journey with these unhelpful, rude, time-wasting, arrogant people.