Curious about running a tube pre into a SS integrated

I know it's been well-documented that there are some who find a tube preamp running into solid state amps the ideal blend of tubey-goodness and solid state impact and speed. 

I have, on occasion (depending on the listening material) run my vintage Luxman valve pre into the "Main" (pre bypass) section of my 509X integrated. On the right material it does offer an extended holographic image and almost magical quality to the front-to-back imaging of the sound stage. 

However, maybe due to the vintage nature of the preamp, it does seem to shrink the stereo sound field a bit, and also does not have the fidelity of the 509X pre. 

I have been considering swapping out the vintage valve pre with a PrimaLuna ProLogue preamp. I suspect that it would give me the holographic depth and sparkle that my vintage pre does, but with cleaner and more expansive sound.

At the same time, I have reservations about the overall synergy between PrimaLuna and the Luxman integrated. Hard to explain, but part of me wonders if it would be compromising the overall integrity of the sound...

I've considered just getting a DiaLogue integrated as an alternate system and swapping out cables when I want to listen to tube magic, but that seems kind of tedious and I'd be sacrificing the benefits of the solid state amplification on the bottom end of things. Plus the 509X makes swapping out line stage very easy with the "separate" function on the unit, so it's easy to do mid-playlist if the song benefits.

Anyone actually doing something like this with a higher end integrated?