There are great collars and then there are amazing collars, I love this one! I have both the 300+ and the 302 (for when I bring both dogs).
The main selling point I love about this one is that since you have two receivers you do not need to have the collar very tight. No matter whether they flex their neck, relax their next, move left/right, there is always a connection. The same cannot be said for other collars (though bungee collars definitely help fix that).
I have also noticed that since there is always solid contact, I do not need to turn the stim level up near as high for her to feel it (most times I'm below 10 on a GSD that is not in drive).
The listing on the page and the customer service information needs updated. This comes with everything in the picture (a good thing): bungee collars, case, etc. They were also cool about changing the cover for free so it didn't match my other Educator receiver.
The only real complaint I have is that you cannot buy an upgraded knob from Educator. The current knob on all controllers require that you look at the screen to see what the stim level is set to, if they would make one of the bumps much larger you would be able to feel approx what the level was. I remedied this by purchasing a knob from Ace Hardware and fitting it to my controller, but it isn't a perfect fit. It does make controlling the levels much easier.
Other than that I think the collar is incredible and their customer service is top notch. I would definitely buy this again!