Generally speaking, individual, 1Password-generated passwords are the safer route. For a longer response, there's both the security angle and the privacy angle to this, so let me give you them both!

Security

Signing in with Google is no different than a typical email + 1Password-generated password sign-in, because your password could be reset by email in the latter, and is tied with your email account in the former; in either case your Gmail account is the key. Personally, I always like to go the traditional email + random password sign-up route for my own convenience later on, because filling with 1Password is so much easier than remembering which Gmail account I used, but the choice is yours.

Signing in with Facebook/Twitter, on the other hand, ties your new account to a social account that might be as secure. That's not always great security-wise, and I'd recommend against doing so in favor of using a strong, 1Password-generated password.

Privacy

Signing in with another service is never good for your privacy. Oftentimes, it'll grant a new site access to view more about you than you might expect—your profile, your social media posts, your name/age, etc.—and that's bad news compared to generally only needing to give up your email address and password.

Hope that answers your question! Let me know if I can help more with anything :)

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It's a little big more secure than using n-times the same password, as you just have one password to change in case of issue, but it's much less secure than having one password per website. If someone get access to your Google accounts by knowing your password, he can access to the list of services you connect to using Google Single Sign On. He also have access to all these services as he is connected to your Google' account. It also means Google can leverage their infrastructure to access the services you connect to using Google SSO. So having a different password per website is a good thing. However, note that the single point of failure still exists with password managers: if someone can access your password manager, he can access to all websites saved into the password manager. That's when 2 Factor Authentication (2FA) becomes useful: more than a password, you also require a code, generated using a USB key or your phone, to access the service. I suggest protecting your password manager using 2FA but also every services, even if the password is saved in your password manager, including your Google Account. This way, even if someone get your password (password manager or google account), he can't use them. I also recommend to pay attention to mail notifications you get when a new connection is made to your accounts to make sure it was you and not someone else. More on reddit.com

Yes, typically it is advised against signing in with your social media accounts because of two main reasons, which you kind of mention. And that is the data sharing that goes on between both websites. This site breaks down how this works: https://www.techlicious.com/blog/should-you-use-facebook-or-google-to-log-in-to-other-sites/ It basically allows these data companies to collect and share more information about you, and by linking all of the services you use, it allows a much more detailed picture about you, your habits, personality, and more. True, websites will get your email address, but which email? Another good privacy practice is to use disposable emails, which a lot of main email providers allow you to do, often called "alias" email accounts. This way you can use different emails for each service, all the while still getting the email sent to the same account. For example, say I want to create an alias with my email [email protected] . I can create numerous alias address, say Email# [email protected] and Email# [email protected] . I can then sign up with one of those emails at one website so that website only has one of the aliases, but the email gets sent to your PrivacyGuy001 email address and if you happen to get a lot of spam you can simply delete an alias and create a new one. One more tip I've found helpful is to name your alias emails by the service you're signing up to, for example, [email protected] . This is helpful because as long as you never use that email for anything other than Twitter and you eventually get some spam you will know which service sold your email to advertisers. I hope this is helpful and if you have any other privacy questions I'll try to answer them best I can. More on reddit.com

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