I've had my SLI-80 for a couple of months and so far have tried the EH KT88's and the SED KT88's. Contrary to what appears to be the norm, I prefer the SED's. In my setup they are a little smoother (laidback?) and, as a result, provided more pleasing treble and midrange response. The EH's may have a slight edge in bass response. I have read a lot of good things about the SED 6550c's and the JJ KT88's (see the AA forums). Also, the Chinese KT88's, sold under various names and model numbers, are beginning to get a lot of good press after historically being considred inferior to the Russian tubes. Upscale Audio and Tube Depot both sell Chinese made "GEC" copies that I may try next for comparison. I guess we're fortunate to have so many good new production tubes to try! Lets us know the results of whatever you select.
Good Luck, Rob
