Right now Open-E only supports Active Passive HA. So if you want to get the most out of your hardware, you will have a hard decision to make about HA. Do you just use replication between the nodes and have data protection? This way you'll get 100% performance but at the cost of no automated failover.
If you go with full blown HA then your other node is there for protection only. You can configure independent targets but those would be unprotected.