I'm afraid it is way worse than that. On my machine I won't even use it because if I put a AE link on a Premiere timeline the render on the non AE parts slows down even though it is not rendering those parts. I just render everything out like the good old days and my renders and previews are lightning fast! Give it try.
I have been seeing insanely high CPU usage on some projects with the playhead parked jsut because something is in a dynamic link is in the project. It's making the whole suite super unstable at this point. I haven't seen it as much since the latest update so I hope its been patched but its only been a day. Also previews get "unrendered" depending on if AE is open as a forground app or a background app. Its incredibly frustrating. Dynamic links also go to "media offline" all the time as well for unknown reasons. Oy.