I am looking at purchasing a pair of of radios primarily for backpacking in a group and secondly as an addition to my BOB. I have narrowed my choice down to a combination FRS/GMRS hanset. Since I was a bit unfamilar with the technology, I did some browsing and research.

FRS (Family radio service)
- up to 0.5 watts power and roughly 2 mile range in theory
- roughly 1 mile range in practise in line of sight
- range affected by terrain and tree cover
- channels 1-7 dedicated for FRS
- channels 8-14 shared use with GMRS

GMRS (General mobile radio service)
- higher power and greater range than FRS
- varies from a handset to mobile station /w or /wo repeaters
- up to 5 watts with handset
- up to 50 watts with mobile
- range up to 25 miles with mobile or more with repeater
- generally requires a radio license except Canada allows up to 2 watts handsets without a license
- 2 watt handsets range has 25-30 miles in theory (mountain top to mountain top!)
- 2 watt handsets range of 2-3 miles in practise
- range over open water is roughly 7 miles for a 6' person to talk to another 6' person due to curvature of the earth and line of sight
- channels 15-22 dedicated for GMRS
- bigger, longer antenna is better because radio wave is about 12.5" tall

MURS (Multi-Use Radio Service)
- de-licensed used primarily for business for location service

Privacy codes (interference illimination codes)
- used in combination with main 22 channels to provide further division and isolation of signal; does not create a private channel but mearly eliminates a lot of the other cross-talking on the same channel to improve intelligibility
- 121 codes usually but some handsets may have more
- channel 1, code 1 is the default setting out of the box but may also be the busiest

Options:
Weather NOAA channel monitoring
Headset jacks
GPS / Radio combo ie. Garmin Rhinos
VOX activation
Noise filters
Keypad lock
Scanner
Calling and paging ability

Is it better to use AA or AAA or lithium ion batteries?
Battery life - varies from 11 to 20 hours depending on combination and type of battery.
Charger options? Double radio charger? USB charger or 120v
I have an inverter to charge items from my vehicle so it matters little to me which way to charge.

Long term storage:
Should I place one in my BOB and one in my vehicle kit or both in the BOB or both in the car kit. If AA or AAA then I would likely use Eneloop batteries for long term storage.

I am looking at a pair of Cobra LI72002WXVP radios that have a claimed range of 45 km, 22 channels, 142 privacy codes, weather channels, 10 NOAA weather channels, VOX, vibrate alert, Hi/Hed/Low Power, water resistant, 2-port charger, L-ion battery, programmable scan, belt clip.

Your opininons and advice????