I have a Recto pre and I love it. I agree with samhill. It sounds super sick with the 2:100 power amp and a Mesa 4x12. That's my current setup.
It probably will not sound as Recto signature without a boogie power amp which will complete the "modern" circuit and sound.
The pre has a "modern" setting, which sounds good direct, but you won't have maximum jiz without the power amp lifting the negative feedback voltage or whatever the modern mode does...