Hey Will,
I'm no expert, but if its working, you probably don't need to upgrade. Typically, you need to upgrade when the BIOS cannot correctly identify new CPU microcode / architecture. If the CPU is properly detected in BIOS and OS you should be ok.
Now, (here's the caveat) If you notice any performance issues or are over clocking, then upgrading would be recommended. This might resolve / enhance voltage problems, timing issues, thermal efficiency, but again if you aren't noticing anything abnormal, chances are you're good. Others here may have more to add.