Scott, ABSOLUTELY these are all personal opinions, but that's what ludi asked for.
Issue 19 of 'Vacuum Tube Valley' ( http://www.vacuumtube.com/vtv.htm ) found the Ei KT90 to be, overall, the best current-production 6550/'88/'90. You might order that issue and LEARN a lot.
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Issue 19 of 'Vacuum Tube Valley' ( http://www.vacuumtube.com/vtv.htm ) found the Ei KT90 to be, overall, the best current-production 6550/'88/'90. You might order that issue and LEARN a lot.
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