Sadly, these have been discontinued. the more modern equivalents seem to be stupidly (Insanely really) expensive,,
They are still available on the bay etc but get them while they are hot. (I have bought a load because I wish to install some additional radiators and I also want some spares for the future)
According to Peglar they have been discontinued owing to poor sales . Well yes, YOU NEVER BLOODY ADVERTISED THEM YOU ******* IDIOTS!
(I really hate it when manufacturers manage to end up end up killing a
really really good product because of this sort of stupidity, I really do... See also-Comfort "Fast Dry". Yes they advertised that, but they didn't tell people how it
actually worked. so most people used it wrong and didn't think it made any difference, which it
really did!

)
I have used these TRV's for many years and I really like them, the only down side is that they are a bit noisy when they do their thing so if you are a light sleeper they may not be suitable for bedrooms. (Also, you need to change the batteries every year, not every two years)
Peglar still sells (For now, but you have to do deep search to find it) the USB dongle that allows one to program then from a PC but they no longer have the website that allows you to DL the software.
(This is a really useful feature)
The unit with the actual radiator valve seem to be almost unobtainable now, but you can still find people selling New-Old stock TRV heads.
If you want to use these, Do not use the adapters that come with them on existing radiator valves unless they are a direct fit, The adapters really don't work very well. You may also find that if you use these with old valves they will end up leaking fairly quickly. You are much better off getting new valves (Pegler terrier) that the motorised heads will fit to directly and doing a clean install.
If anybody buys one of these and needs the SW, let me know and I will send it too you.