I have owned the Soliloquy 6.2's and the Meadowlark Ospreys (both next step up speakers in the line) and auditioned the 5.0's, the 5.3's and the swift in the past. I would say the largest difference if you stated you are mainly looking for acoustics and vocals, is that the Soliloquy's are going to "seem" a bit more forward and pronounced in detail and such when you audition them. The Swifts will tend to seem a bit more laid back and perhaps not as "exciting." I say this due to having lived with both manufacturers, and what caught me on the Soliloquy's up front as a bit more engaging eventually wore on me as not quite as natural once placed in my listening room at home over time. The Meadowlark's on the other hand, didn't tend to overly "impress" me in the store, as nothing jumped out at me, but after listening to them extensively in home for over a year, they have a VERY natural timbre, harmonic presentation and tone. I think this is mainly due to factors such as being time aligned drivers, first order crossovers, and transmission line bass. The bass is also much more articulate and tuneful due to the transmission line, and not as bloated in certain frequencies as I have experienced with Soliloquys. If the Meadowlarks are set up properly, they will soundstage like champs, vocals much more natural and pure than any speaker under $1000 should sound like, and tuneful bass that belies its cabinet. With that being said, pay attention that you aren't placing them in too large of a room. All of my experience was done in home with Unison Research Unico (80 wpc) on both the 6.2's and Ospreys, I did hear the swifts also with VTL integrated and the Soliloquys with a couple different integrateds (in which I can not remember for sure). I have no experience at all with the Concertinos to comment.