Hey I just finished changing my Front discs,pads,bearrings all brand new it's great, I agree with tangofox007 it does take more time, especially if your bearrings are original, those races will be funn to take out by funnn I mean PITA I think mine were rusted on, I had to keep spraying wd40 every little bit I got it down, It requires lots of pounding if you dont have the right punch. ( I heard if you have an oversized socket or something like it you can put it in the hub to fit over the outer bearing races nicely)
I'd say change em to the new ones, The old ones probably went through some wear and tear.
Might aswell while your at the wheels, it takes a little more time but much better results.