It is actually very subjective on the IPS profile used. You can use the default one as a start. A good suggestion is to apply the IPS profile that is applicable to devices you would like to protect. Eg. Use only the IPS signature for Windows OS only if you are protecting just the Windows devices, instead of all other OS such as Linux, Mac and etc.
The Fortinet Security Fabric brings together the concepts of convergence and consolidation to provide comprehensive cybersecurity protection for all users, devices, and applications and across all network edges.