New 2020 V2 hardware for existing alarm Interface conversion


I am interested in the new 2020 V2 hardware to convert my existing 8 zone alarm system in a UK house. I want to keep using the alarm panels and buzzers etc and turn this system into a smart alarm. Will be integrating this into Home Assistant.

Please could someone confirm what I need to order?

Do I need 2 x Alarm Panel 2 (6 zone) and 2 x Interface modules?

Or I could spend $40 more and get the Alarm Panel Pro (12 zone) and add 2 x Alarm interfaces.

As I said I want to keep the existing alarm system and just add smart capability.