Behringer makes some ok stuff, but those inuke amps are severely over-rated, just FYI. Kept to under 1% THD, it puts out ~640W RMS. Still not too shabby, but I personally prefer to have a few extra watts on tap to not stress the amp, but also to keep the signal clean to minimize potential thermal damage to the speaker.
That sub has a 2.5" voice coil, so I don't know how much power compression is being accepted to attain that 700W RMS rating. It does have a 4-layer coil and somewhat decent venting, so it's not too bad for $150.
If you can still get them, the buyout 3" flared ports that they had for $5 are JBL-twins. They use an elliptical flare throughout the entire port, as opposed to a straight cylinder with a radiused end. The elliptical shape is much much, better. So much that Bose sued JBL over their patent on this, and won!
https://www.parts-express.com/flared-port-tube-3-id-x-11-l-with-5-flared-ends--269-165