The way the bias adjustment on your amp is implemented might be a consideration. Some amps are auto-biasing, making matched tubes unncessary.
Similarly, if there is an adjustment for each individual tube, matching isn't much of a consideration as long as all the tubes are functioning properly.
Some amps have only one bias control per channel, meaning all the power tubes in that channel should be matched so that the bias adjustment affects all of them similarly. However, you may not be able to hear or care about any mis-match.
All these consideration apply only to the power tubes, the bias adjustment affects only them.
