The extra speed is fine until it isn't. Speed and inconsiderate driving often go together as well.
Big speed variance to the speed limit both above and below often goes together with inconsiderate driving - I caught up behind someone driving well below the speed limit last night who was driving me up the wall - though partly that was because both times we came to a good overtaking place there was traffic coming the other way - especially the longer straight there was cars spaced just enough to deny me overtaking at the start and middle of it
