I dont know if this is the case with the newer generation Rinos, but not all the models have an electronic compass. What that means is the unit detrmines what direction you need to walk (bearing) buy using the gps reciever so in order to do that you must be physically moving in order for it to tell you which direction to walk.... If you think about this its a real annoyance and can be a huge inconvenience in areas of poor satellite reception.
You have to read the package specs carefully, the units with an electronic compass will be clearly identified as such (much like anything made from titanium will proudly say so). If the package does not state it has an electronic compass.... It doesnt. The decieving thing is some of the more expensive models dont. If I recall correctly, its only the odd number series that have the electronic compass. Like I mentioned earlier I dont know if they addressed this issue in the newer generation Rinos, the ones with the digital camera.
Ive been using my old Rino 130 (with elec. compass) for years its been an excellent unit. Ive had 3 other friends that bought the more expensive 520 model and all have sold them due to it not having an electronic compass.
The ability to transmit your waypoint to another Rino is a huge benifit especially when hunting and you need help. Having a 2 way radio built into one gps unit is one less gadget to pack in the field.