It is potentially confusing because of the differences between Canada, the U.S. and the U.K. Let me see if I can clarify it a bit.
Firstly, in general, all two-way radios operate on certain frequency bands. They can be low frequencies such as Ham radio, high frequencies such as CB radios, very high frequencies such as VHF radios (all aviation radios and marine radios around the world operate in this band,) and ultra high frequencies such as UHF radios (military aviation operates on UHF frequencies.)
There are basically two categories of radios that one can buy for a business such as you are talking (depending on the regulations in each country) or for personal use:
#1 - “Public” frequency radios use shared frequencies where every radio on the same frequency can talk to each other. (There are a variety of ‘privacy codes’ and privacy technology that tries to lessen interference from others, but the reality is that every radio in a 10 kilometer radius is trying to share the same 14 or 22 frequencies.)
Canada and the U.S. have assigned certain frequencies in the 462 MHz and 467 MHz (UHF) band for these “public frequency” radios. They are called FRS (Family Radio Service) and GMRS (General Mobile Radio Service) radios. FRS radios are designed only for recreational communication. GMRS are potentially more powerful but require a licence in the U.S. (but not in Canada.)
PMR (Private Mobile Radio) is the European version of FRS/GMRS. They use special frequencies in the 446 MHz band, and don’t need a licence.
Legally, you cannot use FRS or GMRS radios in Europe, nor can you use European PMR radios in North America.
All FRS/GMRS (North America) and PMR (Europe) use shared frequencies in the UHF band, and the range of all will be potentially about the same, regardless of advertising. This means realistically about 2 to 4 kilometers in urban areas and possibly a bit more in rural areas with trees, houses and hills in the way. Of course, better quality radios will have a better chance of maximizing their range.
This brings us the the Mitex radios. They operate on a special UHF frequency (449 MHz) in Europe that allows full 5 watts in transmitting power, but requires a licence. One could consider these ‘licenced PMR’ radios.
It is important to note that these ‘licences’ are not really radio licences in the true sense of the word. They don’t require specialized knowledge and passing of tests to get a radio operator licence; they are more of a ‘tax’ to use certain frequencies. Also, because of their higher power levels, regulators need to know who people are and where they live just in case they start ‘cross-talking’ onto private frequencies if something goes wrong with their radios.
#2 - The second category of two-way radios are the commercial-class or business use radios that use special private frequencies assigned to that business in that area. Because they use assigned frequencies, they are guaranteed to be interference-free within their licenced areas. They can be either VHF or UHF, and the retailer will program in the specific frequencies that are assigned to that business. These commercial radios require a special business licence plus an assigned frequency.
The confusing part is comparing a commercial (“business”) radio with a programmed frequency assigned to that business in that area, to a “public” band radio that uses a simple licence fee from the government to operate (such as the Mitex ‘licenced PMR’ radios in the U.K. and all FRS/GMRS radios on GMRS frequencies in the U.S.)
When you browse through the great selection from our forum hosts at buytwowayradios, you will notice they have divided the radios into the public band radios (FRS/GMRS) and the private assigned frequency band radios (business radios.)
Consider for you in the U.K., that PMR is the European version of our FRS/GMRS radios.
With the new technology, there is now another option for public band (shared frequency) radios: FHSS (frequency-hopping, shared spectrum) radios. They operate on the unlicenced 900 MHz band in Canada and the U.S., and the unlicenced 2.4 GHz band in the U.K. They can use hundreds of thousands of radios in one area all sharing the same frequency band because they rapidly ‘hop’ from frequency to frequency in milliseconds. Here in North America, there are two makes right now: Trisquare for a consumer-level FHSS radio and Motorola for a business-class FHSS radio. Neither make will ‘talk’ to the other because they use proprietary pseudo-channels (that aren’t really ‘channels’ because they are not fixed frequencies; they are a hopping algorithm.)
This is why I suggested you also look at the Motorola DTR-series. It is a digital FHSS radio that doesn’t require ANY kind of licence but is built to “business-class” (and mil-spec) standards.
This is a bit of a simplistic summary of course and you need to consult the regulations of your country to learn whether the radios you are looking for can be used for business purposes.
The Mitex radios use a full 5 watts of power so they POTENTIALLY have the longest range of any of the “public frequency” radios, but don’t forget that ALL UHF radios are line-of-sight; good quality radios will work better but none will give you any more than the frequency will allow.
It would be great if you could rent a couple of licenced PMR radios like the Mitex and the 2.4 GHz FHSS radios like the Motorola, and see if you like the range.
Just don’t be surprised that the licenced PMR at 5 watts doesn’t give you 10 times the range of the unlicenced PMR radios at .5 watts.