Hmm, it might make some difference on some of the Juniper lines (is the SRX line software-based?) but any of the high-end Juniper products are only using JunOS

Hmm, it might make some difference on some of the Juniper lines (is the SRX line software-based?) but any of the high-end Juniper products are only using JunOS for the control plane. Only control traffic and certain exception cases (e.g. ICMP) ever hit the BSD/JunOS network stack; the rest is all handled in hardware.