Is bias setting necessary on matched tubes?

yes, and they will sound different at different bias settings.

Unless your amp is of the "audobias" type (primaluna is one brand) then you will have to readjust the bias. Matched tubes just means that they are very similair in terms of operating characteristics. Important! If your amp has only one bias adjustment for each channel then it's recommended that you ONLY buy matched tube sets and replace them all when one goes bad. RAM tubes website has a good primer on matched tubes.
Cheers!

Only if you have a fixed bias amp, if you have a cathode bias amp then the tubes will be self-biasing and no bias controls or check points will be present on the amp.

If the amp has bias controls and there are individual controls for each tube, matched pairs of tubes, while desireable, are not necessary. If the amp has one bias pot per pair of tubes then each pair must be matched to prevent current hogging by one of the tubes, leading to premature failure and asymmetry of the waveform.

OK, it looks like my amp the Mingda 368-b90 has manual bias adjustment, one for each tube. I've got a multimeter, but I'm about as new to tube bias adjusting as it gets. Is it easy to do? Where can I get info on how? I don't have any info on the specs save that I'm putting in a set of KT88's. (I think it came with 6550s) Should I just bring it to a guitar shop? Am I being a sissy for not wanting to stick my hands where I know not what? I really don't want to smoke a new set of Genalex Gold Lions or myself for that matter!

Thanks for your input!

Geoff

OK I talked with a repair tech and he said it would be $125 to bias the amp. In addition he's going to go over the amp to see that it's all working correctly. I think it's a fair price for that service, am I wrong?