I have been using the DM 3/7s for about a week now and they do not dissapoint
Comparing to the small but brilliant 2/6 stand speakers, the floor standing 3/7s have a bit more headroom in the middle and a lot more in the low tones. So Dynaudios marketing statement about the DM 3/7 very powerful, dynamic bass performance is true.
3/7 is very detailed and neutral, so I only use the direct pure mode on my amp, no need for trible or bas adjustment. The speakers sound wonderful with all kind of music, classic, jazz, rock, techno or what ever
You don't really need the assistance from a sub in a small or medium size room.
Using the 3/7s for TV audio from my HTPC is pure joy. I can hear a lot of detail, even at low volume. The stereo image is so embracing its sometimes like surround.
Overall I am very pleased with the DM 3/7. In fact I cant find any negative to write about them, but my girlfriend likes the DM 2/6 more because they are small but sound big... She mainly plays pop music at medium volume.
So if you are shopping floor standing hifi speakers in the 2-3000$/par range, don't forget dynaudios "budget" floorstander.