Not all speakers are compatible with tube amplifiers due to the speaker impedance or phase angles, etc. These issues do not affect a tube preamp, although you need to be sure your preamp and amp are compatible, regardless of whether they are tube or solid state.
If I'm looking for "Tube Sound", why would I put a Tube Pre in front of a SS amp?
I'm purposefully not specifying speakers as I would like to know in general terms the arguments for and against. So, to the degree that speaker characteristics could also influence the choice, please explain. FWIW, I do not know a phase angle from an impedance curve so I will try and educate myself as we go along. Hopefully, others may benefit too.