Now I would say that the contrary is true. The KT88, though more expensive and less reliable, have a sweeter midrange on this type of gear.The KT90 is more dynamic and a little "rough" in comparison. However here opinions vary and the proof lies in the listening. If you are really set on KT 88s and don't mind spending the money, I'd go for those types which are on ebay right now and forget about all the rest: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2159973663&category=7275.
Cheers,
Cheers,