Tri-Tronics Electronic Dog Collars Field 90 G2 v Sport 80

[MinnFinn]

I'm looking at new electronic dogcollars. I've got an old Tri-Tronics "The Judge" that loses it's power for any distance in when it gets down near zero or below in late season pheasants here.
I was looking at tri tronics field 90 g2 exp and their sport 90 series comparing features. The main differences I see is that the former has up to 1 mile distance v. the sport 90 1/2 mile rating. Also, the later transmitter runs off of a 9 volt bat. rather that rechargeable. Both collars sound to be similar.
Does anyone have experience with either of these collars and what do you think? Thanks