The LG G6+ on sale right now for just $449.99 until December 23. This is for the Amazon Prime Exclusive model. Keep in mind that this does indeed have the lockscreen ads included.
The LG G6 Plus features 6GB of RAM and 128GB of built-in storage, compared to 4GB and 64GB on the LG G6. Despite what the moniker might suggest, the G6 Plus is not larger than the regular G6.
In fact, all specifications, other than the RAM and storage space, are identical, including the 5.7-inch QHD+ display with rounded corners, the Snapdragon 821 processor, the dual 13MP cameras, and 3,300 mAh battery.