You have to check what are your requirement, what kind of search hybrid solution you need. Currently SharePoint hybrid solutions: Search, Business Connectivity Services (BCS), and Duet Enterprise Online.
In search you have to decide which topolgy you need.
One-way outbound
SharePoint Server 2013 Search services can query the SharePoint Online search index and return federated results to SharePoint Server 2013 Search.
One-way inbound
SharePoint Online Search services can query the SharePoint Server 2013 search index and return federated results to SharePoint Online Search.
Two-way
Both SharePoint Server 2013 and SharePoint Online Search services can query the search index in the other environment and return federated results.
You can learn more about it: Overview of hybrid SharePoint 2013 for technical decision makers
http://go.microsoft.com/fwlink/?LinkId=320740
You should also try SharePoint 2016 beta 2, MSFT announced a better hybrid solution in this version.