Because the Z will take any power you throw to it if its clean power, and if you have to ask about a Z you shouldnt own 1, and if your did want to run a 99z woofer I would say 6k-10k is going to be DUMB loud, may work off less.....I already answered your question in my above post but I will say it again....
The 95 serious goes for around 600$ it really depends on if you have a local dealer, competitor pricing, direct ordering from DD because you have no local dealer...