Daemons in php are and will be, Google:
Try it, read reviews etc. the Problem with demons is that they need more-no, and the monitoring system runs a daemon or not (the server was rebooted, was virginal all the memory, just hovering, etc.) and all sorts of system startup in case of maintenance work in DC.
The decision on cron usually easier and more reliable, but only in one case: there is a guarantee that when the script is run for the crown, the previous script has already finished its work, otherwise the server crash it's just a matter of time or circumstances.