What are your thoughts on hybrid amplifiers?

I have recently set up a completely vacuum tube system and it sounds, well, gorgeous. I was looking at the Pathos Classic One Hybrid amplifier which uses vacuum tubes in the preamp portion, and solid state amplification.
So, to the "tube people" out there, can a hybrid amp preserve the warmth and sound that many of us still think is a function of vacuum tubes, or is it "lost" when the amplification output is solid state?
Depends on the design. I own the Counterpoint SA-220 modified and have heard the Butler hybrid amp. Both amps are warmer sounding then SS amps that I have heard but were not as warm and 3D as some tube amps I have heard - kind of right between SS and all tubes. You need to try out amps that mate well with your speakers to tell what you prefer in your own system as everyone has different musical tastes.

Happy Listening.
I own both tube and hybrid amps. I like both a lot and feel that solid state amps have to have tubes somewhere in the chain. Hybrids vary a lot between models. My hybrid Koras sound like solid state in the sense that they are very accurate, precise, fast, and have tight bass. My tube amp is not like that unless it is running efficient speakers (like the top half of my JM Labs). However the advantage of a hybrid over a typical SS amp is the coherence and emotion. Many of the SS amps I've had didn't pull off the emotional aspect as well. But it all depends.
A hybrid amp is a very good idea if you enjoy tube sound, but have speakers that are not tube friendly. It falls very much in line with folks that use a vacuum tube pre amp and solid-state power amp.

If you do have tube friendly speakers and you enjoy tubes, then it would not be a worthwhile switch.

I suppose it depends on the choice but I have heard the same speakers with an all SS setup , tubed pre and SS amp , a hybrid int. and an all tube integrated . Mine and my wifes listening pleasure increased with the increase in tubes . It turned out to be good bang for the buck as the SS equipment was a few muiltiples of the tubed equipment .
For us less is more .
A hybrid amp with a tube front end and solid state output stage is a good idea if you want to get some tube sound somewhere in your system but don't want to mess with the hassle of a tubed output stage. Theoretically, using tubes for voltage gain on the input stage(s) and semiconductors for current gain on the output stage, is the best application for both, although it doesn't always result in the best sound. As another poster above put it, if your speakers are not too difficult a load, you will most likely keep some aspects of the tube sound (warmth, fullness, dimensionality of the soundstage and instruments, liquidity) and some of solid-state sound (quickness, detail, bandwidth, bass impact). I myself have a tubed phono stage and preamp with a SS power amp, and I seem to get some of both. Although these days the line between tubed and solid-state equipment is becoming more blurred. I had Conrad-Johnson and Audio Research tube gear using 6H30 input and driver tubes with advanced output transformers that resulted in a more neutral sound, which to my ears is preferable to the traditional slow and warm tube sound and bright and flat solid-state sound once the norm.
I own the Van Alstine FetValve Ultra amp. Tube input stage, SS output stage. It is a killer amp, combining the beauty and HF extension of tubes with the control and articulation of SS. Yes, it can be done, and in this case done very very well. I've had other all SS and all tube amps in my system over the years; this one is winner take all.
Is anyone familiar with Pathos hybrid amps?. I haven't heard them (no local dealers), but they have gotten great reviews, and man they certainly look good. Italian chic.
I wrote a review of my Counterpoint NPMs here
Scroll down or search NPM on that page.

My point is that hybrid amps can sound almost
as good as the best tube amps out there but it all
depends on the design and parts used.

Whether the Pathos is mostly a looker vs. a performer
is a different story.
The old Blue Circle BC-28 had outstanding tonality with quite a bit of power. Rarely seen for sale, with good reason.
My KR Audio VA 340 with ss preamp and tube output is outstanding. Especially with the PH-7 phone stage.
I'm one of about three people in the world who are running twin Pathos Classic One MKII (I believe you can use any of the Classic Ones to do this, but on first version must open up the bottom to switch to mono) tube hybrid integrateds bridged to mono. A simple switch on the bottom of the unit gets flicked and wala, you move to 170wpc into 8ohms, and 270wpc into 4ohms! Of course, class A. You want sweet looking? Try two of these babies side by side! I've written plenty on it; just go to my review on the Asylum. You'll actually see two of my reviews; one was for the unit in stereo, the second is for the twin amps in mono config. I've had some very nice tube pre/amp combos come through (I'm a reviewer with Dagogo.com) to date the Pathos Ones are still my favorite reference - at least for now! :). They are QUITE a bit better in bridged mode than stereo and they do quite well with speakers of a variety of sensitivity, from 87dB-ish range to 95. Note well, however, if you are a person who's seeking "realistic" concert levels, then they are probably not for you unless you'd pair them with very efficient speakers. I listen at moderate levels and they've never even come close to clipping or running out of steam. Put them in close proximity and run one remote; they operate in lockstep.
I think the Pathos TT is a fantastic amp, as long as it's a small room/high efficiency speakers. I heard them once with Avalon Symbals (sp) and found it to be a fantastic little combination - great for a small room. I recently tried the TT on my Verities and found it to be really sweet sounding, but the presentation was smallish. A used TT is a wonderful deal IMO.