Well Drubin (and knowing you are local) I have all the ATC Hi-Fi Passive series including the SCM19v2 and SCM40v2 available for demo in our showroom in Fairfax, CA (Marin County). We also have some other interesting stuff like the new NAD M22 Ncore amp. Will also be exhibiting at the CA Audio Show with ATC in August.
IMO depth is nearly entirely a psychoacoustic construct that depends on how far away from the front wall the speakers are. Further you put them, more perception of depth you have.
Resolution wise (which covers off microdynamics) I think these are without peer at their price point. I'm not a speaker designer but I think it is because they are using extremely beefy drivers (large magnets with underhung coils). Take a look at the size of the mid-woofer in the SCM19. Beefy!
Interestingly I think the SCM19v2, which is a standmount, is higher resolution than the SCM40v2. Technically this could be because the mid-woofer in the 19 is the SL "Super Linear" version, whereas the woofer in the 40 is their standard version. May also be partially due to the increased complexity of the passive crossover in the 40. They have the same sonic signature but the 40s have a much "weightier" presentation.
ATC speakers have three main strengths: neutrality, resolution and bass quality.
A lot of people don't like neutral speakers (they might prefer Raidho or B&W, with their explicitly designed "not to be flat" response) but personally I do.
Bass is tight and articulate due to either sealed box or a very low Q port tuning in their larger speakers.
