In case you missed it, Juniper have put out the SRX4600: A 100Gbps single RU firewall

Pretty insane if you ask me. No word yet on if it's x86 vSRX-powered like the 4200 architecture, but I wouldn't be surprised.

https://www.juniper.net/us/en/products-services/security/srx-series/srx4600/

That 1RU form-factor, so hot right now.