The corrugated plastic is the cheaper alternative to outdoor sign replacement panels. It is very durable and can handle low temperatures better than our PVC board. It has ridges in it, as seen in yard signs. The aluminum panels are very durable and meant to last for a long time. The inks are rated for 3 years before subject to fading in the sun. The aluminum panels should last that long... just keep from backing over it with the truck again. Protect your aluminum signs with our protective lamination if you plan on using your sign for a long period of time. It helps prevent the inks from being sctratched and adds a layer of sun fading protection.