Justicia rizzini aka Brazilian Fuchsia

Thoughts on hardiness, please.
Reason: a work colleague told me they had bought one and it was flowering nicely. I looked it up and found a number of sites classing it as a tender conservatory/greenhouse plant outside in a good summer, so I replied I would it kill it within a year as it was so tender. They came back with no it isn't; I've had it in a container outside all winter, in a plant pot against the house wall and it's flowering like mad.

 

Not grown it but was just reading it requires a frost free environment, it doesn't suggest it needs more than that.