tube pre-amp or tube integrated


Existing equipment Marantz SA1153  CD, SACD with headphone jack,Gamut C2r pre-amp,Gamut D200 amp.
Harbeth 30 speakers (love), Fostec 700 headphones (love)
Do I replace Gamut pre-amp with Rogue Rp-5 tube ?  or 
Do I replace Gamut pre-amp and amp  with  tube Prima Luna  HP integrated ?
To achieve tube quality sound or is just doing pre-amp enough? 
Thank you 

piesquare