Due to security restrictions, I would like to determine which of the above options is best suited for me.
I would prefer the On-Premise installation (To avoid creating rules + opening ports in firewall),
UNLESS The On-Premise installation still needs to access an outside/3rd party service for some reason - in that case, the firewall will have to be opened either way.
So i guess my question is does the On-Premise installation consume any 3rd party services? and if so, for what purpose?
Episerver Find is a SaaS product. It cannot run on premise.
The only non-SaaS product in the overall platform is the CMS/Commerce deployment.
The CMS/Commerce implementation will run wherever it is hosted, and will call out to consume or index content from the Find service.
So it doesn't matter how you host, Find will still need to be contactable
Episerver does not sell any new on-premise installations. You will need an old image to be able to set it up. And yes, the latest version still needs to access scripts outside.
The newest release is from 2017 and I would not reccomend setting up any solution with Find on-premise...