it is not necessary to use "real disc"
I use a program called
NoteBurner to convert aac to mp3. This program is a virtual drive as well as a burner and also needs to be used with iTunes.
in iTunes, you can just choose the drive installed by NoteBurner as the burner and then all selected music will be burned on virtual disc and you can transfer to other player directly and do not need to rip back again.