Debian not recommends testing for everyday using. You definetely have to look at the site. Afaik it is basically a bad version of unstable that gets slow updates and it is only for testing purposes.
Packages from debian unstable trickle down to testing in 8-10 days usually if all the other criteria are met. But I have also heard that important security updates go straight from unstable to stable and then come to testing at a later time. When is that later date I have no idea.