I personally do it at 192kbps, it is kinda the boarderline between quality and size.
Unless you have a super mega ultra duper sound system you probably won't be able 2 tell between 320kbps and 192kbps. But most people (including me) can tell the difference between 192kbps and 128kbps, you probably can't tell difference between 192 and 128 if you use standard PC speakers but i have 2.1 and i can tell.
So, Yeah, i use 192kbps as a compremise for quality/size. If you want i higher bitrate than that, i wouldn't use 320, try 256 because 320 is really pushing spacewise.
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