I would like to inform you that a duplicate check on HANA is available. In SAP note 1862997 you can find all the details that you need to set up the duplicate check. Prerequisite is that SAP CRM runs on HANA DB (not side-by-side), and as a customer you have a HANA runtime license so that the use of this duplicate check is cost-free.
In comparison to the duplicate check on TREX also “e-mail address” and “telephone / mobile number” is considered by the duplicate check on HANA.
The main advantage of using the duplicate check on HANA is that you don’t need any data replication.
I heard of several examples where customers use a duplicate check with TREX. But if TREX is not available (no connection), which can happen, users can’t notice this and in doubt create duplicates.This cannot happen if a duplicate check is embedded as it is the case with HANA.