Go for it Stan! Once you go tubes you will never look back. Tubes also allow you to fine tune the sound with tube rolling.

For me, tubes gave my system more transparency, wider sound stage, more warmth (depending upon the tubes I used, and note that not all the tubes that I tried sounded good but each had their own unique sound) depth and presence to the music.
The music sounded more natural and palpable. Any hint of digital edge was removed (even with my SS amp but I'm also using a tube DAC which may be another option for you instead of a preamp. The Tube DAC probably made the most impact in sound for me.).