In general, I like this plugin except that in my environment at least, if I activate the plugin, when users use the "forgot your password" tool--or when I use the emergency lockout feature to reset all users passwords--users are unable to enter a new password that will allow them to login to WordPress again. No matter what password a user enters in the reset password screen, they get a login failed response. This is true even if I disable password policy features in the plugin. The only way to get password reset functioning again was to deactivate the plugin.
I'm using WordPress 3.3.1 and Login Lock 2.2.7, both of which are the latest versions as of this writing.
I submitted a request for assistance at wpsecurity.net, but have not received a response.