Since my 2203KK has the stock KT88 that seem to be dated 2007 I am contemplating switching them for some new ones. The amp has some road wear and indications it could have been a gigging amp before I purchased it and I have had it for a year now with some fairly regular high volume use once per week and practice volume use more often than that. I see the EH quads of KT88 for around $140+. There are also offerings from Mullard, Svetlana, JJ, Tung Sol, Psvane...and of course the reissue Genalex Gold Lion. I have biased the amp up hotter than stock but not crazy, it's at 68mV per pair now. Can anyone honestly say the Gold Lions are worth the extra price over the competitors? I'm not opposed to spending the extra but if it's just flushing $40-60 extra dollars down the toilet then I would rather not.