Excellent article here from the Royal United Services Institute, whose catchy headline I shamelessly swiped.
In case of TL;DR, the gist is that their digital tactical radios don't work very well, and are NOT widely deployed.
One thing caught my eye, and I have to pass it along: It is possible that the delivery of the Azart radios has been troubled by corruption.
The Azart is their 6th generation, walkie-talkie-type secure radio.
I'm shocked, I tell you.....Shocked!