It is not possible to give a definitive answer to the question without actually trying them out on-site. The maximum range is around 2 miles (3 kilometres) dependent on several factors such as such as the size of the radio’s antenna, the frequency band the radio is using, the surrounding terrain, and whether the user is indoors or outdoors
All PMR446 radios are legally limited to 500mW transmission power, which means that all brands will have around the same range. The range is reduced drastically when the radio signal passes through solid objects. Within buildings the range may be as little as 1/4 mile.
Business radios transmit well over 2 miles and when repeaters and antennas are used, range significantly improves and can reach all the way to 30 or 40 miles.