Terran Surveillance Station

With the recent uploading of the Terran and Protoss Tech Tree images, the flood of information coming from BlizzCon 2007, and the updates at the official StarCraft 2 website, we now see that the Command Center has two available upgrades in the form of an defensive structure (Planetary Fortress) and in the form of an informational-intrusive -- a little term I came up with as it's scanner sweep ability allows you to see cloaked units and delve into the fog of war -- structure (Surveillance Station.) With this second upgrade available we can see that a Terran player must choose which one he or she would like to have, which begs the question:

Is it best to build a Surveillance Station when you have neutral observatories and other sensing apparatuses? Or would building a heavy defensive structure be the best viable option? I know that situations are forever in an ebb and they will almost definitely be different every time. But is it really necessary to make another structure that allows us to sense and view things? I think yes, the Terran Surveillance Station is as essential to any player as it allows for direct scanner sweeps over any location you want (based on StarCraft 1's scanner sweeps) and knowledge is key in any RTS game.

What do you guys think about the Surveillance Station? Do you think it is necessary? Do you still wish there was a ComSat Station add-on so you could just piece it to the Planetary Fortress? Discuss away!

 

Surveillance station on the main, planetary fortress on expansions.

 

I don't know how to answer because I don't know which is the upgraded one and the one you start off with.

 

both are permanent upgrades.

 

No I mean which one do you upgrade from the first? Because the first can only detect where it can see, while the other can detect in the fog of war.

 

what do you mean sensor/radar towers? sensor tower is first, then radar tower.

 

Oh, nevermind, I know what they mean now. I was thinking of something else.

 

Depends, if you can rush to planetary fortress and you know your opponent is gonna rush your workers, you go for PF. Or even in late game you could use the PF as part of a turtling technique.

 

Can you go back to regular comand center or something (I know that you can sell the planetary fortress for 100% minerals, but can you just sell the planetary fortress and not the whole comand center?)? And does it build as fast as it did in the demo?

 

no, permanent upgrades.
i think build times were shortened for the demo.

 

I think you'll probably want to use PF on like resource outposts to help protect them. And maybe the SS on your primary base if your defenses are good enough.

 

I thought that was the point.

 

any1 know how much HP boost the CC gets from PF upgrade compared to SS (if it gets any)
and how much dmg PF does?