Was able to compare the Shuguang made KT-88/98 (which are superior built and sounding than other KT-88 types including the so called new production Gold Lyon Russian power tubes) after 3 months or so compared them with GEKT-88 also Chinese and the improvement was a major step.
I have not tried sinlge getter KT-88 since the 88-98 has one side getter and another (halo up on top) now the GEK-T88, has 3 getter and it sounds really good.
I've found a guy selling the GEC "originals" blue sticker which reality says they are originally made in china outsourced fromm Genelex in the 1980'2 qndd 90's (SOUND FAMILIAR??) the British KT-88 GEC have been out of reality reach for the last 10 o 12 year at the every least.
Today's choices are clear, GEK-T88 from China is a steal for the price quality is very musical, organic presentation, smooth top end, bass authority etc. etc.
Sounds really good, that's what I can say, now . . mind you the little that I know about tubes is that nobody can predict how a particular tube will sound in the context of the particuloar circuit and also interaction with the other tubes in the equipment, and that is a fact.
example some people swear by Mullard small signal tubes (12AX7) now sometimes Mullard sound with no bass, no top end to speak of and no timbre distinction, is that a problem with the Mulards?? i don't think so is just the inetraction with the other tubes and the synergy of that interaction. on that application teh best sounding 12AX7 was indeed a Sylvania 12AX7 NOS that can be had on e-bay for a few bucks, Luckily I have good friend tube addicts that we exchange our tubes to see what works best with what other and the surprises are many that way . . .
Another word of advice, some of the new generation of chinese amplifiers made with tubes are really of superior quality, the problem, most of them are designed to work off 110 Volts. this country of ours hasn't had 110 Volts for at least 15 or 20 years, in my neck of the woods the norm is 123 Volts for the grid, si using a step down trasnformer or simply a Variac is a must otherwise reliability of these amps becomes a factor, since plate voltages multiply, in reality a plate voltage of 450 Volts for a KT-88 tube ends up being almost 570 volts with the extra voltage coming form the grid, that blows up anything.
Go ahead discover some of teh wonderful Chinese tube amps you see in the market doem of them based KT-88 and 300B are truly wonderful pieces, than in time maybe swap capacitors for betterquality for a top notch sounding tube amp thta couls easily rival $10 to 20,000 esoterics for under $1K, now you know it . . .
enjoy tubes they are the real music and tone of real instruments vibrating in space, somehow trnsistors no longer cut it for me, they can sound very nice but not as real, melodic or tibrally correct as the tubes.
Compare $15,000 SS amp to $1,200 tube integrated yhou'll see for yourself.
Hope it helps a little;
God Bless!
Gonzalo