I don't have any trouble seeing how important the woofer inductor (low-pass) is sonically. What surprised me was that the high-pass inductor is also very important.
I tried a number of different chokes on my woofer before settling on the North Creek 10g, and the type of choke used in the low-pass has a major effect on sound quality, perhaps even more than the cap in the high-pass section. Of course, I didn't try a CAST choke and I don't doubt that it could sound better than the North Creek but it's a question of where to draw the line. My woofer has a 3.0mH and the high-pass has a 2.2. The CAST versions would cost over $1000 each, i.e. $4000 for a stereo pair. The North Creek 10g costs about $200 each or $800 for all of them. This all gets rather expensive pretty quickly!
That said I do think the CAST caps have proven to be good value. In other words, the improvement in sound quality has been worth the cost. So I won't rule out the inductors but I am resisting.