Hi,
Source addr persistence persist based on the client ip of the incoming packet.
In an HA deployment of your bigips, you will need to mirror the persistence table from one device to the other to keep persistence info when there is a failover.
With cookie insert persistence, a cookie is inserted in the response to the client and it works for http/https only. You don't need to mirror this persistence as the entire information is retain in the cookie value. I suggest to actovate the cookie encryption option to avoid backend guessing through cookie value decoding