A lot of these newer coil over shock systems seem to last a lot longer than the older shocks. I remember in the 90s replacing OEM shocks with just a little over 12k. Now manufacturers reccomend replacing your shocks between 50-80k depending on the make/model.
BUT! If it aint broke do not fix it comes into play when it comes to some things such as shocks. you may also be coming into shocks starting to fail and the noise is just the start. I would go with KYB or Bilsteins for these types of shocks. If you decide to change them. The KYB is a popular brand at Car Quest and I have bought them for less than generic Monroe for a lot nicer product. I just hope KYB hasn't dropped their quality.