Have used this before, it deteriorates with time, after a long time, it will start to bend in one direction and ultimately we will throw it away, still for at least one year it will give cooling from the harsh sun
Don't replace the discs. The life of the disks is more than 1 Lakh kms unless you have not replaced pads and damaged the discs. Anyway remove the discs and take to a lathe to check if ok. Usually the dealers try to fool people by asking them to replace the discs. 90% of the time they are fine. Even if they are not the lathe can polish them and make them flat. should not cost you more than a few hundreds.
Same thing was told to me for my Rapid. Checked it and it was fine. since I had opened it up, I changed the pads.