Hi bro,
Long post coming up - I guess I can comment on em since I'd used them for quite a while some time back. My experience were limited to their famous System 240 MK II and System 360 models - a 2 way and 3 way matched pair components respectively. There's also the cheaper System 240GT with a pair of 6.5 inch midbass units using stamped steel basket as opposed to the more complex and expensive cast steel basket 7 inch mid bass drivers of the System 240 or 360. Which one did you audition, bro ?
So, looks like you've been bitten by the Danish Butter Cookies bug, eh ? The Dyns are rather accomplished all rounders IMO having toyed with them in the past. To my ears atleast, they faithfully reproduce music in a very natural and almost original studio monitor like quality. In many ways, they are tonally and dynamically accurate, exhibit excellent transient response and are extremely phase coherent while being easy on the ear and non tiring for extended periods of listening. They excel with almost all forms of music genres except on heavy metal, hard rock & techno where listeners may dislike the Dyns apparent lack of attack or pace as compared to Focal or MB Quart drivers.
The MW170 mid driver is well known for its mid bass reproduction capability while being very neutral and uncolored in it performance. These are one of the most neutral sounding drivers in its price bracket which means poor quality recordings will not be so easily tolerated. The MD100 tweeters are not exactly my favourite - I find them a little too subdued and lifeless but the general perception about them are of a smooth, neutral and accurate performers. The supplied X250 passive crossovers although made with fine internals/components are rather simple in design and pales to the newer generation passive crossovers that offers tonnes of tuning and control options. In my experience atleast, the crossover itself is power hungry and its crossover points set seems to suit on-axis use best which may prove to be an obstacle for you. In fact, most Dyn 240 users that I know of has long ditched the passives and went with the active route for tuning flexibility and more driver control.
Do pay special attention to the tweeter/midbass placement /layout as this has a huge impact on the overall performance of the babies. When "tweeked" and set up right, these speakers will reveal EVERYTHING, but in the most musical way. The little things you didn't hear before, like musical space/silence between notes, vocal tecniques and instruments is nothing short of amazing. And till today, despite being quite an old driver design, very few drivers in the same price bracket are able to rival the MW170 midbass unit for vocal handling - in many ways it's also due to the unique motor structure/construction (massive 3 inch voice coils), giving them exceptional control over the cone / dynamics. The general idea is that Dyns are power hungry components and they do thrive of power - lots of it. Running on passive crossovers, you're looking at a minimum of 130-150W per channel from a decent 2 channel amplifier though they seem to sound even better with about 200W per channel. Ditching the passives means that you'll have more option and a decent 4 channel amp with 75-100W minimum per channel should do the job nicely. BTW, you'll also might want to bear in mind that the Dyns can be rather amplifier fussy so you'll need to shop for an amp that suits that overall type of sound that you're trying achieve. In my experience, both my Genesis amps - Dual Mono (passive set-up) and Four Channel (active set-up) were perfect partners for these babies and complemented them beautifully.
And yes, sadly even Dynaudio has fallen victim to the slew of fakes that seems to flood the Asian market - please verify the authenticity of the speakers that you're buying and ensure that it was brought in thru the official distibutor. Lelong.com is a good place to start for those want the fake sets - I've not gotten my hands on them yet to hear exactly how they sound.
Cheers,
VaN.