I wish I were better educated, and better able to discuss this...but I'm not. However, ADAM designer Klaus Heinz swears up and down that active designs are not only more efficient, but are actually better sounding - so much so that he even makes active versions of the ADAM HiFi line available. Interestingly, I'm getting ready to translate a whole paper he wrote on why that is, which will hopefully give me a better understanding of this subject - I'll be more than glad to post some of it here when I'm done.
What I do know is that there are a whole bunch of people whose ears and opinions I respect that seem to think that working on active monitors (not just ADAMs) is the way to go. I have a difficult time believing that so many top engineers and facilities - all of whom can certainly pick and choose what they want to work on - are using active monitors for any other reason than that they believe these are the best tools for the job.
That being said, everyone has different ears and different tastes...and if passive designs work better for you than active designs, I don't think that's any more wrong than the people who prefer their active monitors.
dB
ADAM Audio USA