Have had a Whistle for 5 years but I think it's dying. Have to charge it way more often now. Almost daily.

Any others worth a look?

I have two whistles. Love them. Had to replace one because the battery started to go.

Best available
Garmin Alpha 100 and T15 collar.
-9 mile range but elevation, trees, etc- expect 2 Miles
-Simple to setup Geo Fence anywhere you go- alerts the remote when they cross the fence.
-Tracking has a bread crumb trail.
-It’s a full out GPS with tons of features
-Birdseye view available of terrain
-tone, vibrate, shock, or mic.
-battery needs to be charged every night but worth it being able to know it’s always tracking the dog.
-works anywhere on the planet. Doesn’t use any type of cell service
-no service plans
-can track up to 15 dogs at one time.
- handheld and collar have replaceable batteries.
- waterproof for handheld and collar
-Made to hold up to full time hunting dogs in any condition.
Nothing else really come close after digging through all of the tracking collars.

Pfizer
Moderna
J&J

Seriously  though Garmin makes some good ones.