The discussion about loudspeakers is very similar to processors

Each loudspeaker has their own sound so the preferences will be quite subjective.
I have a friend with a production studio who bought the Mackies HR824 on MY suggestion. I listened to them at the local hi-fi show and thought they sounded very good and open. But he never really liked them for professional work he does. While they are good as a hi-fi speakers and for music such as jazz and classical, he could not mix good on those and went to Genelecs 8050s with the sub.
Genelecs don't like to call their products speakers - rather monitors. And that's what they are. They might appear "cold" to some, but they are designed to tell the truth and be as transparent as possible. In a production and broadcast studios (which is their primary market) that's what you want.
The mentioned friend also tested for a few weeks the big PMCs with the Bryston amplification. Again, these speakers have their advantages, but he didn't like them better than Genelecs. There are other manufactures to be mentioned for example Adam Audio with their ribbon twitter philosophy or Klein & Hummel. I personally like Dynaudio Professional as well. Each have their own sound and I'm sure lots of followers.
But there's a reason everybody knows Genelec... What I particularly like about them is the serious R&D and innovation that goes into their products. From things like Iso-Pod absorber and positioner (reminds me of something Steve Jobs and Apple would design) to unique innovations such as directivity control waveguide and minimum diffraction enclosure. They've practically invented the professional active speaker with all the benefits of active crossovers, optimized amplifiers for each driver with direct control, protection and other things some already mentioned in this thread. That's on one side.
The other is the build quality. Unlike many other products on the market today, Genelecs are designed to last. They don't believe in designing a product that will fall apart in a few years and will need to be replaced with a new model, thus generating cash. They believe in making a product that will last for decades. And contrary to the popular belief that this is not commercially viable, they have been extremely successful and profitable with that philosophy thus far, even in the recession.
Their speakers are hand made. Each part is tested and measured several times during production and no speaker leaves the factory without being fully tested and calibrated so that it meets the strict standards. Do you know which other loudspeaker manufacturer does this? Most are not even burnt in...
Their 8000 series with die-cast aluminum enclosure is completely air-tight sealed to prevent unwanted resonances - complete speaker is tested with several bars of air pressure applied to bass reflex port to make sure it leaks no air on the joints. Some of their drivers (ie, the new mid-high coaxial driver for the latest 8260) is hand made in the factory as no driver manufacturer could produce the driver that would meet the specification they wanted. That speaker recently won a TEC award.
Finally, the company has strong ecological values. From the environmentally sustainable manufacturing process itself, to design goal that the products need to be almost completely recyclable.
Now compare that to Behringer...
Regards,
Goran Tomas