I have had my Bass pans for over five years. Yes they have a few spots, these are spots that were slightly discolored due to the reaction pee has with metal. Everything is clean and there is no smell. The Bass pans if wiped regularly with a vinegar solution do not hold any sort of odor. Yes, anything will look worn after a while but I can probably get several more years yet out of my pans.
The pans are noisy if you allow them to bang against the bottom wires. What I did to prevent this was I actually cut the Bass pan box to fit under each of the pans. The cardboard from the box kept the pan from banging against the metal wire of the cage. After I just clean them, before there is bedding or anything else in them.. they are again a little loud but once you put stuff in it's not loud anymore. Think of it like how things moving on a wood floor can echo into the rooms below. Put down a rug and tada much quieter.
I love my Bass pans. I could not imagine having the plastic pans as so much more mess would get all over the floor. The tall sides of the pans keep so much of the mess inside of the cage.