If you had to choose: tube amp or tube pre-amp?

To me it depends on the size of your room and the music. In my uncle's rectangular listening room which is quite large (sorry I don't remember the dimensions) he paired a pair of Threshold monoblocks with an tube Audio Research preamp. Heavenly sound with any kind of music. For me in a nearfield set-up where I was about 6-7 ft away I was able to use a solid state Accuphase C200 preamp with a Baldwin tube amp that had a power tube complement of 6L6GB/6V6GT tubes that sounded pretty awesome.

If you worry about the financial cost of re-tubing an amp (although perhaps only equaling the annual cost of leaving your SS gear ON ALL THE TIME), you need to factor in the MENTAL cost also...thousands of suggestions and opinions about re-issues from Russian factory workers on the Volga and Chinese fancy presentation boxed electron beam bottles, antique esoterica harvested from rusty Swedish radios and Cold War East German helicopters...it's insane, but worth it if you can take it. Get clearance from your therapist, and be prepared to lose all your friends...*sigh*...

Wolf for president!

I think it's hard to say which is better since system synergy comes into play.

What I have found is that with difficult to drive speakers which need to eat up quality watts and lots of it, I find a SS power amp gives me enough juice to get the dynamics right while the tube preamp gives me the lushness and 3 dimensionality in the soundstage.

I use an ARC 5SE with Electrocompaniet Nemos to drive my Thiel CS3.7s.

I also use an Ayon CD5S with Plinius SA Reference on a second system to drive the Lenehan ML2 Reference