I have both tube and solid state and agree with several here that diversity is good. I use solid state for my CF3's as it appears that they like a lot of power and did not sound great at 30 tube watts. Grand Funk Railroad sounds awesome on them. On the other hand I use tubes on my Chorus II's and a they produce a 3D soundstage I have not gotten with solid state yet. I typically start listening to tubes at lower volumes and then finish the night with solid state.
i must admit I find tubes to be a lot of fun and picked up a 1929 Majestic radio recently and can,t wait to get it going. The real problem here is WAF as it is hard not to get addicted to either!