Something elese I forgot to mention: A well designed tube circuit will not have any more distortion, noise, etc... than a solid state circuit. The "tube warmth" thing is more of a marketing gimmick than anything else. Yes, the Manley and the Vipre sound great, and they are tube, but there is a reason they coust a couple thousand dollars. A $75 Bellari is not going to be in the same league. (Not that it isn't usable, it's just not going to be the holy grail of warmth simply because it has a tube in it)
Real, well thought out tube circuits are expensive to implement when compared to solid state. You can get into a really good SS preamp for about $500/ch. If you want to be in that same quality range with a tube preamp, you are sitting closer to $1000/ch. When you are just starting out and you will only have one outboard preamp, it is best to go with a SS preamp because you get more bang for the buck.