Thanks for the plugin.
By default this is using "302 Moved Temporarily" rather than a 301 redirect for quick redirects.
I am not sure if this is intentional.
I have overridden this by setting "Make ALL Redirects this type:" to "301 Permanently moved" but is confusing as the setting says "(Quick 301 Redirects will always be 301). That makes me think it would use a 301 even if this was set to "Use individual settings"
Not sure if this is a bug or how it is supposed to work but it would be good to make the hint text more accurate as I imagine most users won't double check it.