Do you know what the bias setting on your amp is? If your tubes burned out, would you know how to get the same sound back as you had before?
The amps bias makes a critical difference and you really should know all of the bias settings for each amp you own and what the voltage number of the tubes that are in them, especially if you like how your amps sound.
You can check the number of the tubes by looking on the tube box (you did save the tube boxes, right?) it will be written on the end.