I agree with torn.  I am 99% sure you have to use a laptop and agremote to configure the 162 unless you have access to a machine with a pro600/700 and do it through the RDI screen(essentially agremote).  Easiest is to bring it to a dealer if you haven't worked with it yourself.  Hardware wise you just need to power it up and connect the 9 pin to the laptop (via usb to serial adapter or native serial on the laptop) and run agremote  If you don't have the cables can be a PITA.

Reason for 5 hz vs 10 hz is because it's more messages than necessary.  10 hz takes more "brain power" to process and "overkill" for row flow.  That being said, unless running large prescriptions and individual row shutoffs I don't see how 10 hz wouldn't work.  

GGA, RMC and VTG only.  Otherwise the 20/20 will have to read and discard all the other messages.

Someone can fill us in as to "why" 5 vs 10hz but this is what I was told.