Truckers use CB but very few motorists. Ham or amateur radio required individual licenses and hand held radios are limited as to signal output and antennas used by the Federal Government to protect the users' little gray brain cells. If you have a license the radio can only be legally operated by you and not by anyone else.
GMRS radios are a one time 5-year license (at this time) that provide the same output as the hand held Ham radios but anyone in your family can use the same license, even grandkids. They are a little bit better than the FRS radios which are good for only very short distances.
The radios sold in the USA will have false Watt output numbers that do not correspond to their actual signal output which may be 95% lower. The "4 Watt" radios often put out only 0.1 Watt of signal power.
The Ham, GMRS, and FRS are all line of sight transceivers so they are blocked by buildings, trees, rocky terrain, hills, etc. which is why 1/2 mile is the best that can be expected almost anywhere. They will work great in flat open areas like most of Texas for example but be poor when used in hilly or wooded country or in large cities.
The Ham have the advantage of being able to take advantage of some relay stations that are privately operated in some areas for a small group in a community. The Ham and GMRS can provide much higher signal output with a base 12v radio installed in a vehicle and can make use of an external antenna for communicating over a much greater distance.
The combo GMRS/FRS radios are the most versatile and easy to use but the quality and true range varies widely. The best ones will be over $100 each but some people are happy with the $20 ones when used around a campground area. Check the reviews on Amazon.com for the different models and you will get a good idea of which ones work better in actual use than others.
