WWW Streaming

We are streaming WWW audio ("AudioClip myAudioClip = www.audioClip;"), We need your advise on how it is recommneded to save the file after it's done downloading completly, and if it's possiable to track it's progress while switch scenes (we are switching scenes while downloading).

is it good practice to save the file to Application.persistentDataPath? I'm unable to understand how to use AssetBundle on this type of cases, it can be 100 different type of audio files that we will need to stream/download and save.