Radio range
In general, all current RC transmitters are capable of the same range as all put out the same power. The difference is in the receivers, some are much better than others. Doing an accurate measurement on this at the power levels we work at is very difficult at best and few if any modelers have the equipment that will do this. Check the sensitivity of the receivers as quoted by the manufacturer, this is usually quoted as microvolts/meter or millivolt/meter. This is far more accurate than anything most of us are capable of measuring unless we have access to a very expensive RF lab. Also remember, running your transmitter with the antenna at any position other than fully extended does put additional strain on the output stage of your transmitter and is not recommended for more than a minute or two for quick range tests. You have probably noted that the back of your transmitter gets hot when you run with the antenna down. Don't do it unless you have to and then for very short periods of time. Mean time to failure approximately doubles for every 10 degrees C of temperature rise in the output stage.