What I like better about the 10" active speakers is that they seem to clear up a lot of the problems that the 450's have. In my opinion, the Mackie 450 is a pretty bad sounding speaker. The problem with the 10" ones is that you lose a few things. You lose a little low frequency response, and a little output power. Personally, I would rather have less low frequencies that sound better than more that only create mush and other issues. I can not compare it to the passive ones cause I have very limited experience with the passives. The only reason we have any of the Mackie speakers at all is that for a while we were Mackie dealers amongst other things (we started as RCF dealers, but when RCF sold to Mackie we picked up that line not knowing how bad the change was going to affect things).
From what I understand about RCF, is that they were a driver company that made drivers for lots of different speaker companies including EAW, even before Mackie bought EAW. They also made a few speaker cabinets, but the only ones that really seemed very useful was the ART series of powered speakers. Since the Mackie buyout, I beleive that RCF has once again become it's own entity. From what I can tell once Makckie bought RCF, the original owner and designer went on to either found or greatly improve upon the D&B Audiotechnik line. The D&B stuff sounds incredible and personally for a small line array, is the only one that even comes close to the Meyer, and Vdosc ranges. Now I believe RCF is marketing once again under the RCF name and my limited experience with their new stuff has been pretty good. It easily sounds much better than the Mackies, although it may not be quite as inexpensive. Their newer wood built monitors also sound pretty good. Keep in mind when thinking about D&B that their seems to be a couple differnt D&B companies. I do not know if they are related, but I do not think they are. The D&B that makes the "opera" series plastic powered speakers sounds nothing near what the D&B Audiotechnik stuff does, but then there is a big cost difference as well.