My experience is the sound is different.
My initial systems were entry level SS and I acquired McIntosh C2600 tube preamplifier - it was a dramatic improvement. Using an analogy the music was clearer - I could easily hear specific instruments in the context of the song and had a better sound stage of where the musicians were playing.
I've also heard very good SS preamps. I recently auditioned one as I consider upgrading and evaluating a pure linestage preamp with separate phono stage.
Listening side by side to a series of songs, the sound was different from the McIntosh and to my ears it was 'clearer' and frankly my first concern was would the sound be irrating so I played some songs where there could be harshness.
Ultimately, I think the difference is the audible nature of distortion. SS can have much less distortion and a whether tube or SS a well designed tube preamp uses the distortion within its sound singature.