ATC make some of the best speakers in the world.
One key thing new in the last 2 years is their new tweeter, which sounds exceptional. It has no ferrofluid, very powerful magnets and dual suspension.
The one you've linked is from their professional line, and is active with onboard power amplifiers, in a very plain painted / textured black cabinet. The SCM19 is the "domestic" version and uses essentially the same drivers but in a real wood veneered curved sided enclosure and in a passive format. The SCM19 was well liked by both Absolute Sound and Stereophile, for what that is worth.
I've installed the 19 and 20, both measure extremely well (very flat and neutral), have exceptional resolution...competing with speakers many times the price on that metric. Bass is very tight, both 19/20 are sealed box. Both are voiced "flat" without any boost below 100Hz.
I should update my sig, but we are dealers for them. Have 7, 11, 19, 40 and 50 (both active & passive) available for demo.