while there are people above who have noted the importance of time alignment, I am sure that they are aware of the mechanical benefits of going active:
When running a passive crossover, the amplifier stage has to push full bandwidth, from low bass to high treble frequencies, and has to push through the resistance of a crossover. With an active setup, the amplifier stage has several octaves less of frequencies to cover and doesn't have to push through a passive crossover network. The result should be much cleaner sound with less overall distortion and probably greater volume capability before the driver starts audibly distorting. From a power perspective, active amplification is absolutely the way to go. Time and phase alignment are also useful, but going active alone without TA is still quite beneficial.
