Pads, maybe, I had to replace the pads on my Wife's old POP after just 16k, but the factory fitted discs were absolutely fine.
I always swap out my own discs and pads these days because I want to be as sure as I can be of the quality of what I'm putting on the car. Sometimes, completely dependent on the marque of car mind you, I will buy genuine discs/pads as put on the car at the factory. My Saab for instance, I only ever replace the pads with genuine GM pads which I buy off the famous auction site for a fraction of the price they'd cost from the dealership (and yes, they are always genuine, not cheap copies!).
As far as discs are concerned, I am very wary of a lot of cheap Chinese iron that is out there. I tend these days to buy EBC discs (though I won't use EBC pads because they didn't last very long on our old MX5 and seemed to finish the discs quickly too). EBC do have a very strong reputation and the discs supplied from the UK are I believe all manufactured here in the UK using quality iron.
I too would get a second opinion on what the dealer has told you and I don't mean going to your local High Street do it all makes tyre and brake shop (although there are some that offer a lifetime ownership of pads replacement deal), a friendly local mechanic with a good reputation will do. You can easily buy quality discs and pads for the 500 (dependent on which trim), for about £65 and of course if you are mechanically adept (such as me
), you don't have the associated labour cost.
Clearly letting a dealership swap out your discs and pads will undoubtedly come with an eye watering bill because at the end of the day, this is exactly where some dealerships make the money. It really isn't a hard or rocket science job to do for a competent home mechanic. Swapping out front discs and pads on a 500 shouldn't take any longer than an hour, certainly didn't take me any longer than an hour to change the discs and pads on my 9-3, half hour each side, and that car is twice the size and weight of a 500 Twinair!