Hi Greg,
If it's not a UHF 'walkie-talkie' or handheld device with equal to or less than 500mW (0.5 Watt) RF output with a fixed or non-removable antenna then it needs a licence. (PMR446 regulations.)
Pretty much simple as that really.
See Ofcom for further details but be warned you'd have to fair old wade your way through a lot of documentation. (Probably why so many 'Chinese-Whisper' info to each other.)
Of course there'll be those that profess 'knowledge' about everyone using them, not to worry about it, no one's gonna get caught, etc. etc. Up to you in the end really without a leg to stand on if you are ever caught.
Usual disclaimer applies as in I am not a qualified legal expert, offering no legal advice whatsoever, only assisting with where you can find out further information for yourself.
When searching Ofcom for answers look for "PMR446" and "IR2030 Licence Exempt Short Range Devices or SRD's.)
Manufacturers and suppliers are supposed to provide relevant information for the country they are sold in and their regulations.....some do, others don't.
So up to you in the end.
I'll await the hordes exclaiming quite the opposite but seeing the lacklustre state of the forum recently I won't hold my breath. (Although it might make a few peer from under their rocks.
)
They are great radios for cheap VHF/UHF Amateur Radio use on appropriate licenced frequencies but dual band versions are just as cheap and of course there's a lot better stuff out there for Amateur use.
Not much help was I Greg?
(Let's just say PMR can be a lot of fun if there's like minded individuals in radio range.
)
All the best,
Victor