I've been progressively eliminating tubes from my system. First the phono preamp, then the preamp, now the power amp. If I stay the course, the only ones I'll left to deal with will be in my guitar amps. Heat has never been an issue for me, but the longer I ran tubes the more I heard them, and all I want to hear is the music. And they fail, they always eventually fail, whether by flaming out or just contributing little noises. I don't want to be distracted or even potentially distracted by my gear when I'm listening. Soundwise I don't think there's really a need these days, just an aesthetic preference which I'm weaning myself off of (and gaining clarity and control in the process). Plus I can enjoy more music more often if I'm able to leave my rig turned-on and warmed-up. Yep, for now I've pretty much had it with the 'romance' of tubes, and audio in general: I just want my system to be a dependable music-playing appliance, nothing less but nothing more either.
Anyone else evolve beyond tubes?
Over many years of owning both solid state and tube amps/pre-amps, my most recent high end system makes me question the need for tubes at all, except at the source! My Mcintosh C46 pre and MC501's driven by an MF A5 CD player into Dyn" C4's with MIT Magnum cabling produces music of great beauty and dynamic swing. I even demo'd some of the newer tube gear available for comparison...not even close. I think modern, well designed solid state gear is superior overall...at least with a tube output stage in your source!