What is your amplifier and which preamp models are your considering? I have a DMC30SS in the context of a Spectral system and prior to this system had an Accuphase C2800 driving a set of Lamm amps. The Accuphase preamp is very easy to listen to, has excellent resolution and tends to smooth out edges so that there is nothing harsh. That model was outstanding but bested by a Boulder preamp, which I therefore acquired. The Spectral preamp is highly resolving, transmits a wealth of information effortlessly. However, in the wrong setup it may not seem to work right. I say this because I had the DMC20 14 years ago and at the time it did not seem to match my other gear at all (can't remember what it was but it would have been a solid state amp).
I would say that the Spectral preamp is as smooth as I would want it to be (there is nothing objectionable about its treble and its reproduction of transients is remarkable). I don't think you'll hear the attack and decay as clearly with an Accuphase preamp.