Anything higher than 1:1 that enables you to run a 3.5-4.1 axles and end up with a 2.7-3.2 final has got to be a big plus both for a performance increase and an MPG increase.
About the only negatives I've read on the GV is the already posted reverse grenade.
Unless there is a better way, I think I'd wire a cutout triggered by the backup light circuit.