Is it worth taking a targeted placement at a university?

The question isn't quite right, because whether it makes sense completely depends on what's waiting for you after graduation. If the organization sponsoring the targeted placement is a company where you actually want to work and find it interesting, then it's a great option: you study for free and already have a guaranteed job lined up. But if you take a targeted placement just because "it's easier to get in that way," and then realize you don't want to work at that organization, it becomes a real headache - you'll have to either fulfill your contract obligations or pay a penalty.