also depends on how much hard drive you have ;-)
it IS worth it, obviously 'cos it's better... BUT, when you have something other than apple, you can't listen.
some people think nothing of having two copies of music, i only want one. so i say, AAC @ 320, it will play on everything i have. in fact i just deleted some ALACs & reripped them.
some will think i'm daft then for having ALAC & then downgrading. but the difference is tiny, so, meh