ATC SCM40A speakers

those are passives not the active version the op was looking at

Incorrect, sir.

They are the SCM40A active speakers. Retail $13,000, selling for $8000.

Less than a year old. 

This is definitely one of those situations where you must simply go out and  thoroughly audition both pairs of speakers and let your own ears be your guide.  Happy listening. 

@audiotroy ,

Just came to me you might be addressing @audphile1 and not me.

In that case; correct, sir.

OP,the ATC SCM40A is an ACTIVE speaker..The B&W 803 D3 is a PASSIVE speaker..
Are you looking to DO AWAY with your amplifier & move to a SELF AMPLIFIED(Active)speaker?
 If NOT,then you want to look at the ATC SCM40 PASSIVE (NO "A" in model # ),which are world class speakers with,IMO,a much sweeter treble than any B&W & maybe a slightly richer mid range,though B&W has a pretty decent midrange...