Definitely a good service. One thing about the data you get from them, though. I'm sure you know this but others might not. If your email address shows up in a list, that doesn't mean your actual email account has been compromised. If it says that your email was found on for instance a DropBox breach, the password you used for your DropBox account is the one that's likely compromised, so that's the one you need to change. If you're using that password for multiple accounts, change all of them, preferably to unique passwords. Password managers like Dashlane and 1Password make doing this VERY easy.
Great points! For many people, they have one email address. If your email address/password combination was compromised at any one site, any other site that uses the same combination (which could include your email account!) could be compromised via "credential stuffing" so keep that in mind.