I have implemented 8180 sip alerters with IC in the past. They are built as paging gateways off of the LPI. You should have no problems setting up multiple zones with the Algo speakers. You can use multiple 8188 per zone if you leverage the multicast master slave features of the speaker for each zone. This will also save LPI Zones. You can also us this feature for the "Page All group" zone.
The one problem I have found is that LPI does not support the message priority feature of IC, and the sip alterers will not work properly if they LPI tries to switch the multicast stream in mid broadcast.
I wish ALGO would develop a IC compliant SIP device to use. I really like there products.
If you do not require set paging on your zones you don’t even need IC to set up a overhead paging system with the Algo 8188. Just register the 8188 as a 3rdparty sip device to cucm and call it. The newer firmware adds support for multiple paging DN and multicast streams.