Could I please have any feedback from users of Fortinet devices?

We've having real difficulties with filtering, usually centered around Google, and the current mindset is that Fortigates are not fit for purpose. Our ISP has been chopping and changing things to try and resolve issues with no luck, upgrading and changing firmwares, attempting different block patterns and we've ended up with having a couple of days of disruption with no SSL sites working (You can imagine how fun that is with no webmail at all, no finance/internet banking/payroll for the admin folks, no youtube, list goes on) or having to use Bing instead of Google as a compromise.

Wondering if anyone else has had similar issues, if they feel Fortigate can do the job properly, if they've taken any extra steps etc.

No-one knows how things work in schools like you guys hence the post here; our ISP appear to be trying their hardest but no doubt this is one of the many reasons they've already stopped using Fortinet on it's own and gone over to Lightspeed instead.