I use Rino 550 garmin's GPS 2 way radio.

Pros:

great GPS
You can easily share your position.
No costs
High potence 0.5, 2 and 5 watts.
Can use AA batery
Text message

Cons:

Cost a lot. Near 1000 Bucks a pair.

Motorola talkabout mr350.

Pros:
Cheap
Use AA batery
Ease To use.
No costs

Cons:

Low potence.
No position sharing.
No text message

Delorme inreach explorer.

Pros:

Use in real emergence.
Global coverage.
2 way messaging
Can use as replace GPS (dont have maps! Only tracklogs)
Real time position sharing.

Cons:

Cost.