I have had luck. But i have also see the very ugly. Staffing firms that push push push, and then tech interviews (if they are looking for a the "right" person for 6 months or more) Thats where its dead. Yes its their prerogative , but then you start pushing your resumes out more. Then end up taking a job that takes you on the spot, but you (other the glassdoor, and using linkedin to talk to former employees) never know what your really getting into. Its so one sided, just make sure you have the skills so pass the tech part, as that weights heavy (even though most questions, they wouldnt know themselves sometimes and would be on the internet in 10 seconds themselves) due to what is required of Full stack software engineers, DevOps, even sr network admins