I'm only just now listening to the pod cast for Inside Job and Patch. They mentioned how the worst part of Plot Devices is the hunt for them and then mentioned the O Parts from RID which I forgot even existed until they mentioned it. Personally I don't agree with that. I think the worst part of a plot device is when the entire episode is focused entirely on the Plot Device. When a random object of the week has more screen time than every character combined that's when I hate the plot device. I don't mind plot devices when they don't take over the episode. That being said the O Parts are a plot device that lasted threw an entire series and the fact that I didn't even remember they existed means they were a good plot device. It's not like in Unicron Trilogy where the Mini-cons/Energon Stars/Cyber Planet Keys were the entire focus of the series. I mean they went to the extent where the plot devices powered up the Transformers where as the O Parts in RID they just find them and then don't use them till they have all the parts collected. So it's not like they were constantly on screen even when they're not actually important to anything going on in the current episode. Basically G1, BW, BM, RID, and Animated all had good plot devices. Armada, Energon, Cybertron, and the Live Action Movies all had bad Plot Devices. Prime has had both good and bad depending on what episode you're watching.