It's good, but it's not perfect and it might not be enough.
https://www.chicagotribune.com/news/ct-covid-19-saliva-tests-university-of-illinois-20200827-asst6cyxjjg2lpdnjhunzwjlbe-story.html
They also use their own new saliva based testing system, which is cool.
I live in Chicago and have been impressed by our state's handling of this, although it's far from perfect. The state does a LOT of testing per capita and has a regional/target approach to handling outbreaks.
All that being said, it would absolutely not surprise me if UofI was asked to shut down if things start to look like they're getting out of hand. Downstate is kind of a mess, and although the Uni might be handling things ok, venture too far outside that bubble and you're going to run into unmasked vectors.