The lack of flexibility it gives for our careers page
Some of the "quirks" such as if you update things via the candidate profile page it doesn't automatically translate to the "talent manager" page.
It's the worst ATS I've ever used for automatically spotting duplicate profiles. I've had situations where there's been over 4 separate profiles for the same candidate
The Chrome plug-in for importing LinkedIn profiles frequently crashes and doesn't work with LinkedIn Recruiter.
Compas isn't a preferred talent partner with LinkedIn recruiter so we don't get the additional cross functionality between the two that we'd get with another ATS
Limited reporting functionality for specific candidates associated with reqs.
Other annoying quirks include the fact that the most recent resumé on a candidate profile isn't automtaically the one shown in the resumé viewing tab, even if it's set as the default.
The quick search toolbar for candidates is utterly woeful
Unless you have budget constraints, I would suggest using an alternate system for recruiting needs.
Even simple and cheap recruitment CRM systems (such as RDB) do a far far better job