What do you see as the downside of tubes?

Well Brian congrats - that is what it is all about. I take it that none of your children or pets were injured, and your house didn't catch on fire? Thank heavens for that bit of luck given that you were in the presence of not just one but TWO tube amps.

Unsound mind, I guess you can add being mesmerized by the music and not hearing the fire alarm to your list of tube amp sins.

I think owning tubes is like being in love with someone. Sure there are compromises, but when it's right, you can't possibly imagine being without them. Rfogel has the right idea. I run the same Atma tube amp and preamp as him. I have been an Atma-sphere user for 20 years (my first set of their amps were almost 20 years old and in perfect condition when I sold them to buy the very latest version - I have since even become a dealer for them) Over the years I have tried some very good SS amps and preamps, and while they were quite good or even excellent, going to the tubes simply always bettered them, in many different ways. The tangible sonic characteristics, and the ones that can't be described, in that one finds themselves so much more "into the music" that goes beyond audiophile attributes.

Also I think owning a set of good tube gear can get one off the audio merry go round much more easily. I think it would be an interesting poll to see who upgrades their gear more often, tube or SS users. If my hunch is correct, than that would mean a considerable cost savings by not buying new gear so often.

I think when i was younger, I was also more impatient. I didn't want there to be any downtime fussing with tubes, and it annoyed me when I had to. I just wanted to listen to music.

Now I look at it as a process, and more of a hobby than just strictly listening to music. I know I may have to hunt down a microphonic or blown NOS tube every so often, but it is seldom and in my mind well worth the investment of time, for the 99.9% of time when I am enjoying the system so much.

Ultimately a well designed tube based system doesn't just make recordings sound nice, but makes them sound like the real thing.

Oh, and as far as tubby or uncontrolled bass, I recently posted about hearing an extremely well regarded speaker, with a well known SS amp that sounded thick and undefined in the bass. Another user posted back that that same combo produced those results when he heard them too. So it isn't just tubes that in the wrong combo can produce a lack of controlled bass.

To reply to the OP, the chief downsides of tube components are as follows:

1) you will have less time for your wife/GF/etc., leading to resentments if they are at all insecure.
2) your career will suffer as you spend way too much time listening to music instead of working.
3) your net worth will be diminished as you spend more coin on LPs and CDs, etc. than you did before emerging from the SS forest.

We put a Standby feature on our amps so that you could keep the amps warmed up 24/7 if you wanted to- and rated the amps accordingly. The nice thing about tubes is that if you want the system warmed up properly, it only takes about 3 hours, where solid state requires about a week. So IMO, why waste the energy- I don't run the amps 24/7 because I don't *have* to for best sound, though I certainly could and have done so many times in the past.

As proof of that I just came home from vacation and found that I had left my preamp on while I was gone. Sheesh- I hate wasting the power, but the preamp was none the worse for wear.

Anyway, if the tubes are in Standby (filaments but no B+), they will make very little heat (unless your amps use 6C33s). Most of the heat a tube amp makes is due to the class of operation, not the filaments. IMO if heat is what is the priority, your system is going to sound like it too. I would not call that a high end system- a high end system is all the stops out to create the realism and experience of music. To do that will make heat, tube or transistor not withstanding.

There is a common tendency to trade convenience for performance; digital vs analog and tubes vs transistors are examples of this tradeoff. If there was any way that transistors could be made to make the music that tubes can, I would not be making tube amps- but I put up with the base nature of tubes because also therein also lies the closest you are going to get to the music.

AMEN!!