Aha, I completely forgot this was only a monoblock, I saw the L and R inputs and I got all excited (jumped to conclusions). The 8awg came with a wiring kit and it was 17 feet... man I need that 4awg to come, now.
My mids sound good (much better since they only have to put out enough bass to fill in the low mids), and I completely forgot about phasing, the HU actually has phase control (albeit only 0 or 180), but I'll see what happens when I switch it and if it makes a difference I'll adjust it through the amp.