Any good reasons to use transistor phono stage and line level preamp instead of tube ?

Im with bigkidz, I have always found good tube gear to image and soundstage better, more 3D. 

I have solid state (Whest PS30RDT) and valve (inbuilt Atmasphere MP-3) phono stages.
The Whest is dead quiet, very smooth, detailed, has a huge soundstage, and layers like crazy. It does big stuff incredibly well, and is my go to for rock, electronic, classical.
The Atmasphere is definitely noisier (faint valve rush at low volumes) but once the music is playing it's not noticeable. And its not quite as controlled on the really big stuff. But it has a texture and grit that I find more lifelike, and is simply gorgeous on smaller scale, acoustic, jazz, and human voice.

I love them both and use them both. But if forced to decide on one, I think I'd go for ...... nah, not telling :-)

To me live music sounds warm, no high order harmonics there to give your ears that unidentified edgy sound. Supposedly tubes convey the music with less high order harmonics. So there's that.
For some it may be a bit of a pain to search out and implement the right tubes, mixing and matching to find the right combo. For me it's like cooking up some gumbo. When the ingredients are spot on just can't stop eating. Last night I ate for about 3 1/2 hours. Delicious.

Laissez les bons temps rouler
gumbo good! 
Transistor good
Tube good 
listening to derek and the dominos on wax, great! 

inna,
The reasons you listed are pretty good reasons in & of themselves. I get great 3d imaging & a wonderfully textured presentation (as well as pin point imaging, even at the edges) with a modest audio alchemy PPA-1 with PS-5 power supply. Prior to this I was using a Sonic Frontier signature, for years. Much more detail (without being bright or harsh) with the AA. Haven't looked back.