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


Besides lower noise and no need to hunt for particular NOS tubes. 
inna
I have both tube (Manley Chinook, Jolida JD-9) and solid state (Musical Surroundings Nova Phonomena) phono pre-amps.  

The size of the units may be another factor to take into consideration. 

The Phonomena takes up less space than the other units, but on the other hand I can stack a turntable on top of the Jolida.  There are of course some very small tube units like the Project Tube Box and large solid state units. 

I leave my Jolida JD9 on most of the time by the way.

My space is limited and size and form always play into my decisions.
For very low signal they are much easier to keep things quiet than using tube amplification.  I am a big tube fan.  I do use a tube line stage. Ralph Carsten has commented on this before 
Sound quality is different. Not better, just different.
From a practicality standpoint, transistors trump tubes every day. Lower power, longer life, lower noise (usually) vs. tubes.

Is a particular transistor phono pre better or worse to your ears than another tube phono pre ? That's a judgement call between you, your ears and your wallet.

Best,
E
Tube phono stages are going to more susceptible to RFI if you are near a radio tower. In other environments maybe no issue, but when I lived 1000ft away from one, four or five tube phono stages all gave me trouble. SS phono stages all eliminated the radio signal that rode along with the music and could be heard between tracks and during quiet passages. For years I've stuck with tube line stages and ss phono stages and am happy with the approach. Cheers,
Spencer
 No tubes usually means less maintenance and no cost of replacing tubes when needed.