I have the single 12 ported Fox Box and my entire system is built specifically for SQ. That being said, I have all the SPL I could ever want. I’m using an R-Series Alpine 12 with a Rockford Power 750-1. I’ve never the heard the netbox, but again...I couldn’t be happier using the Fox. It looks great and freaking sounds amazing. I’m able to control the gain on my sub channel using a JL remote with my TwK D8. Hopefully the amp you mentioned has a remote gain for the sub...it’s a must have since all music is different. I promise you won’t be disappointed with the Fox...no idea on the other.
Link to my build with pics of sub enclosure. I highly recommend the JL FiX-LSA-4 to ensure there is no noise from the HU. I used custom resistors first, and had to go back and add the LSA-4 to correct the issue. Now it’s PERFECT. Good luck!!