I generally agree with both responses so far. Only thing to counter Jason’s comment is that while his statement is generally accurate, I would say that coloration depends on the design of the tube preamp or amp. I have heard very colored tube preamp (e.g. Cary SLP-05) and not so colored tube amps (e.g. Audio Research REF 150 SE), but in most cases, a true tube amp likely would add more coloration that most tube preamps.
Depending on the speaker’s impedance curves and sensitivity, one may prefer to match them with tube or solid state. Many opt for a tube preamp with a solid state amp because it can deliver a harmonic presentation while confidently controlling a wider variety of speakers. If the speakers are hard to drive, the requirements of a tube amplifier tends to go up exponentially, as does the price.