As REN V owner I also would like to say that its indeed an unbelievable pre.
But alot of people asking/fiving opinions online regarding preamp online don't seems to understand that its also about component matching.
I have several pair of speakers at home, one I'm currently using is Klipsch Forte IV. Being horn system there is no need tp question the speed/PRAT of it, so upstream I can use something alittle toward warming side. Not slow (don't know what some people meant VAC is slow), juat a rag warm.
Now if I'm running some 83db giants 5-ways dynamic speakers, I'd prob need something else (SS or ARC ref) to make it toward neutral.
Also, people do not understand the difference between a transformer coupled preamp (like VAC) vs capacitors coupled preamp (ARC). Diff pros and con. I myself would do transformer-coupled all day everyday.