Wordpress multisite with jobroller
I have build a network using subdomains architecture with wordpress.
Example Tree:
JobRoller.com (network)
-domain1.JobRoller.com
-domain2.JobRoller.com
-domain3.JobRoller.com
i have mapped real domains to these virtual subdomains and can access those through primary mapped domain(using domain mapping plugin)
On the other hand my exisitng three domains: domainA,domainB,domainC. running JobRoller and are having 3 different wordpress installs with their own databases, where there are 1000's of posts and users.
Through forums i have built an understanding that i can import these 3(individual) databases to 1(network) databse.
My questions:
1) How scalable is the wordpress network and MySql single databse with respect to JobRoller theme? Can this single DB handle 10,000 users and their 100,000 or more posts?
2) Can i give an employer access to all 3 domains in the network using a single username, while job seekers remain isolated to individual sites.
3) Job Posts on 1 site should not be displayed to all other site sites, ?? is this possible with single DB?
4) Can we use individual databases and still be able to use network features and give rights to employers to have one username for all 3 sites?
Please give your opinion.
Thanks.