Sitting en banc, the Fifth Circuit has reversed its decision earlier this finding that 18 USC 16(b) is unconstitutionally vague. Instead, the court differentiated 16(b) from the residual clause of the Armed Career Criminal Act (declared unconstitutionally vague by the Supreme Court in 2015 in Johnson v. United States), and declined to extend the decision in Johnson. The circuits have split on the constitutionality of 16(b) following Johnson, and it seems likely that the Supreme Court will need to take up the issue in the near future.
The full text of United States v. Gonzalez Longoria can be found here:
http://www.ca5.uscourts.gov/opinions/pub/15/15-40041-CR2.pdf
My blog post about the earlier 3 panel decision in the case (reversed by the en banc decision) can be found here:
http://www.sabrinadamast.com/journal/2016/2/12/fifth-circuit-finds-18-usc-16b-to-be-unconstitutionally-vague