Thanks for the feedback, guys. Looks like I'll go with the mtx thunder 564 and dedicate each channel for a PL-7. Any comments on that one or something better for not a lot of scratch? ($300 on fleabay is about as high as I want to go.)
Just so I'm clear on this, the Audiocontrol 4XS can be used to set a midpass for these, right? I'm wanting to stay with 4 independent channels in order to use the spiffy time correction stuff in the Alpine HU. (Just picked up the 7995 yesterday.) I'd really like to go with the DXS, but two of those would be spendy. Next month, I'll add the tweets and an amp for them.
Thanks again!
Dan - finished the apeaker adapters today. Easy-peasy with the right tools.