Basic vs Multi-Site SSO

I am still finding these models confusing. Specifically when it comes to the benefits of multi-site configuration. I'm hoping someone can clarify. Here's a 2-site example:

• I have a Dallas site with a local SSO server isolated, separate from vCenter
  
  
• I have a California site with a local SSO server isolated, separate from vCenter
  
  

In the first scenario, I configure both sites with Basic SSO:

1. My assumption is Dallas Administrators manage the California site if I add the Dallas vCenter server to the California SSO server correct?
   
   
2. I also assume this means authentication to the California site from Dallas goes over the WAN to the other SSO?
   
   
3. If so, how would performance compare to say managing a 4.1 remotely in linked mode as I do now?
   
   
4. If the Dallas SSO goes down, no one can manage Dallas until it is back up correct?
   
   
5. If the Dallas SSO goes down, a Dallas engineer could still manage the California site by redirecting the client to California. It would just be over the WAN correct?
   
   

In the second scenario, I configure Multi-Site with Dallas as Primary SSO:

1. In this scenerio a local replica is maintained at remote sites. As I understand this, the only benefit is local authentication to remote sites improving remote autehntication performance not really management performance. I see no other benefit.
   
   
2. Has anyone compared performance differences. I somewhow thought after the initial remote authentication token exchanges would be limited and not a huge performance hit.
   
   
3. In Multi-Site, if the Dallas SSO goes down Dallas is still inaccessible until it is back up correct?
   
   
4. In Multi-Site, if the Dallas SSO goes down, a Dallas engineer would still have to redirect the client and work over the WAN correct?