Does KT-88 runs hotter than 6550?

Did anyone ever have premature failure with their Sonic Frontiers Power series when using KT-88 instead of stock 6550? In theory they are inter changable, but KT-88 does run at higher plate voltage (true?) and can run the components inside the amp like resistors or caps harder.

Or it is just a rumor?

I am getting ready to retube my Power 3, don't want to make 16 wrong mistakes. I understand EH KT-88 is the current standard for reasonably priced KT-88 and beats the EH 6550 by a long shot.

Thanks guys.

David