Anybody got any info or experience with the new Barnes LRX Long-Range Hunting Bullets 284 Caliber, 7mm .284 39 Grain LRX Boat Tail bullets?

There already is the 145 grain LRX bullet for the .284 caliber so I'm not sure what is the advantage of 139 grain vs 145 grain in the same model line design/caliber.

Anybody tried the bullet out of 7mm Rem Mag or 7mm-08?