"..Just a warning to anyone in the UK thinking of buying "Bluetrack" CD-R's.... DON'T !! The quality of these discs varies considerably from box to box (and even sometimes in the same box. I have used them in the past without a problem, but recently they have gone downhill to the point where I will no longer buy them, even if it means I miss out on burning a CD for a while.
The latest batch I have had used a light green dye in the, and lighter coloured patches could be seen after burning which meant some areas of the CD were not readable. Not only that, but 3 of the discs in the 10pack were so poorly manufactured that rubbing the top (label-side" surface of the disc caused silver to peal away leaving a see-through hole in the CD !!
I have sent the discs to various places in the UK (one to Bluetrack, one to Which? magazine - a consumer magazine, and one to BBC TV Watchdog program). I would strongly advise against this brand of disc!