KT-88/ 90 choices to replace my new stock tubes

Thanks for your suggestions, isnt the factory tube in the quicksilver V4 pronounced Shuguang as well. Is this penta one also a chinese tube, and if so would it most likely be superior than the stock (shuguang-I think) KT-88 in the quickies. Where can I find this penta shuguang closed plate KT-88 SC, and I wonder how it would compare to say the KT-90. I know the KT-90 is said to increase the power in the V4, but will they retain the lush and textured midrange of the KT-88.

I had 6550s in my integrated amp when I bought it, but replaced them right away with EH KT88s. The sound was much fuller and in my opinion more enjoyable. FWIW

I second Jeff's recommendation. The Penta Shuggie's are fabulous. Just be sure to request solid plates without holes.

I have had the EH KT88's and was not impressed. I think the Chinese made Valve Arts that I use sound great though.

Use KT90's and your midrange may suffer somewhat. The kt90 is a more alive sounding tube. If you like to go in that direction then the kt90;s are for you. I had good responce with Valve Art kt-90s. Valve art kt90's sound great in Hurricanes. Kt 90's (series 2,) sound best in VTL 300 (need a boost in highend dynamics) My rogue Zeus Electro Harmonix are best, ect.I woulnt be too concerned with power output.
Ive found out of all these listed amps i sold them all and kept a rogue Magnum 120's, MUCH faster and less tubbey then the lot. Hope this Helps.