please notice my disclaimer that i AM quite opinionated, and must concede that the performance of the dart preamp is probably as good as people say it is.
unfortunately, I am limited to the time i heard an older rowland system with avalon ascent-II's, properly set up at a dealer's showroom. he played some charlie byrd on a SOTA turntable and it sounded pretty magical. this was quite some time ago, of course. i had to smile when he said "imagine what it will sound like in a couple of weeks 'cause the speakers haven't even been broken in yet." i was looking at a system that was way beyond my reach- the outboard crossovers on the avalons were something i could never have imagined a speaker company would consider necessary. the other pieces of the system held me in a similar state of awe. anyhow, the preamp was a rowland consummate which was the current state of the art (around 6 or 7 grand without phono). listening to charlie play his classical guitar with such an abundance of subtle nuances revealed was pure bliss. i imagine that having "that sound" in my house today would certainly be more than adequate (with a nice alblum collection of course). i often place myself in an audio "time machine" when i read the praises of equipment that tops the current list of the "best of the best", so i am not trying to deliberately be arbitrary or argumentative, but simply trying to offer a different point of view based on a number of experiences i've had over the years. my brother has a pair of pass aleph 1.2 mono's for example, driving sonus faber extremas. putting on a cd or an alblum over at his apartment, even with mediocre acoustics, has such an organic quality, that i become completely absorbed by what i'm hearing. plus he shares my love of jazz with equal passion and has a cd and record collection to die for. his preamp, btw, is an aleph-p which got killer reviews when it came out- well deserved if my hearing is worth anything.
I need to stop somewhere, so i'll do it now. if the dart provides as much pleasure as i have experienced from the rowland and/or the pass lab preamps, that's fantastic. that it can do so much more than that i can't get my poor brain around, but i am sure that it does. anyhow, i just don't like the color scheme...! (kidding).