Somebody was given a price quote a while back for the VP150 crossover including shipping costs and it was around $70 IIRC. The M80 crossover will be more expensive than that and multiply that by 2. I'm not sure what they charge for drivers including shipping but lets say an average cost of $35 per 5.25"/6.25" driver to keeps things simple. The 5.25" being estimated less than $35 and the 6.25" estimated as more than $35.

If you do the math for the M80 with a crossover X 2 and woofers X 8 you are looking at a pretty hefty cost involved for the upgrade and this is probably a low ball estimate.
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