Oh, and before Spiderplant corrects me
There's also a Pace 1000b STB used in Bromley areas which is different from the 1000 internally (more like the 2000, in fact) but still uses the TWTV remotes.
Another thing I forgot to mention is an easy way to tell which type of remote control you have. If it's blue then it uses standard RC5 remote controls, but if it's black/dark grey it uses the TWTV system.