It was decided that the SAM site needed to be redone, so Aircraftkiller did just that. It is similar to before, but this time features much more detail.
SAM sites are just as important as any other base defence, since they are the only defence that can hit air units. If you let them get destroyed, you leave your antire base open to air attacks at any time.
The model and textures were both done by Aircraftkiller.
See here for more details.