Given our track record with Juniper, "drop everything and patch now" is a foolhardy approach, especially with something as important as a border router or firewall. I wouldn't apply any of their patches without seeing a long track record of safety. With heartbleed there was an unknown level of risk that they would be attacked; with any given Juniper patch there is a known risk the network would just go down.
Of course, given the choice, I wouldn't select a Juniper device to route packets to a doghouse, and would never place one as a mission critical node on any network. Then again, that's not my choice to make, just one we have to live with.