BE is ~$90, and you're not going to get a huge return on your investment. If you just have cash burning a hole in your pocket ... then yes. Otherwise you're better off saving the money and putting it towards a new mobo/CPU combo.
THG only recommends upgrading CPUs if they are 3 tiers higher in their hierarchy chart. That being said, the upgrade would only be a 2 tier upgrade, so only you can make the call. However, here is an info page that may help you decide: