the only reason i could think of that might make an external xover better than an HU crossover is that the external xover might offer steeper slopes. I prefer an HU because it is at the tip of your hands. Unless of course you have a H701 with the remote control, etc.what makes an external crossover like the digital AC better than the HU crossovers?
x 2...why do u wanna use a midrange, with that large format tweet? the dayton tweet can play down to the 1800hz range and the mid can pick up there too. i'm gettin ready to do an active setup btw. just run the dayton mid and tweet, and get an amp for each (love my zap's). then get an eclipse 8455 and you're ready to go, install.
Dave
x2 on the Eclipse 8455, much better then the pioneer imo. Another option that you may want to check out is the Alpine 9835, that is a great deck also that can do what you want.