HRM 310 can mow up to .37 acres and the HRM 520 can mow up to .75 acres at a time before needing a recharge.
You can choose from random, directional or mixed cutting modes. Miimo stays on your lawn thanks to a perimeter wire you install. Starting at $2,499, the Miimo is on sale in the US as of June 2017.
Miimo is not a new robot and has been in Europe since 2013.