I have bought a NEC 3540A with the firmware reported by Media Code Speed edit to be NEC K035 27/04/05. However on the drive it is written May 2005.
The drives DOM (date of Manufacture) doesn't need to be the same as the date of firmware.
What you see reported by MCSE ("K035") is not a firmware revision. More likely the bootcode for your drive as seen by MCSE.
It's a general saying; "if ain't broken, don't fix it". Out of this my suggestion to you is to learn more about your drive and burn some discs before even begin to think about "upgrading" firmware.
We have a good FAQ with a firmware section. Make a good read in there and all your questions will be answered.