The H series has an improved chipset for gps reception. It has nothing to do with the radio portion. The H series does only show up in the 5x0 models, however, and all the 5x0 models do have higher wattage on the radio than the 1x0 models.
FRS/GMRS is the radio service that the rino's use. FRS is unlicensed and limited to 1/2 a watt. Use on GRMS frequencies requires that you get a license (~$75 from the FCC for 10 years I think) Both are also limited by the antenna that is built in and cannot be legally modified (FRS restriction). The new chipset is for the GPS and does not change the FRS/GRMS range in any way.
Range quotes of "miles" are WAY optimistic for normal use. Miles might be obtained line of site – from mountain top to mountain top, for example. Fractions of a mile are more likely on the ground, and less in terrain that blocks the signal.
Car to car is even worse as the car shields the signal. Car to car in the city is worse still – maybe a block or two.
If you are looking to get further, you'll need a GRMS license and radios with more power and external antennas. Better yet, get a Ham license – cheaper, and you have access to much more frequencies (GRMS is limited to a handful of channels) across the entire RF spectrum! There's a forum here about GPS and Ham radio as well.
I am a ham, and have enjoyed using APRS (Automatic Position Reporting System) which is the ham "equivalent" of position reporting on Rino's, but much more. There are gateways to the internet that allow anyone to look up my position online, 2 way messaging, etc. Lots of fun!
- wow, thanks for detailed explanations about FRS/GRMS.