Dave_b, this post made me curious and I just happened to have 2 XLR pairs of M1000i's laying around that I put back into my system replacing the Acoustic Zen reference II XLR's. The most noticeable difference was that the Zen's have a slightly smoother midrange and highs and a touch more definition in the base. The M1000i's on the other hand, seem a little "faster" giving guitar strings for example a little more "speed", "attack" and "bite". The Zen are a little smoother and warmer sounding without giving up resolution or dynamics. Focus, depth, width and height of the soundstage remained the same. In my system (BAT VK-250, VK-31SE, Meridian 588) switching between the Totem 1's and Arro's, the results were consistent and I prefer the Zen's. In a system that needs more "zest" or "jump" the M1000i's may just be the wake up call. At $200 as compared to $500 Zen's the M1000i's are an excellent "budget interconnect" and hold their own across the board, especially considering they can be had much cheaper pre-owned.