I have to say burning to CD, then re-ripping from iTunes just doesn't work in quality terms - you really do lose a lot in that process. I know I've tried it having bought a few albums through iTunes before I realised the DRM meant that I was limited when using music I downloaded legally compared to music I might have downloaded illegally (honestly guys - not a good strategy for encouraging legal downloads!).
Nowadays, I just buy the CDs and rip from them direct. If I was being a slightly shady character, I might recommend, if you want a song instantly, download it illegally whilst you wait for the CD which has it to arrive through the post and then, once it does, delete the illegally downloaded track. Naturally, I could never endorse such a practise because of the illegal nature of circumventing such DRM which is only hurtful to the honest consumer as opposed to the mass piracy merchants. And of course because making a copy of the CD in your iTunes once it has arrived is illegal for very obvious reasons known only to those who make the law and can't keep up with modern (and I mean modern only in terms of the last 30 years or so since the invention of the cassette tape!) practises.
Sorry, slightly drink inspired rant over!