i had a hosting provider that only installs it per app on request, and i have to go through tons of back/forth support QA before they finally understand what im talking about and install it.
then i asked, why not put it as an alternative? they said, they won't do it, only per request basis. they also didn't get that zend cache is not zend guard loader. they have the cache, just not the loader.
they also said it's a dated tech, and it will not get a php7 support, so futureproofing with zendguard is difficult. plus not getting the speed boost from php7 due to zendguard loader is also 1 of the downside.
so yes, please re-consider it.