Edited: it’s been 5 months and now the battery is gone. We were diligent about unplugging it when it was fully charged. Never let it overcharge, and now it does not run more than 10 minutes without saying the battery is dying. Not worth it. 

The rest of the review was after a week: it’s been great! Not too difficult to put together and my sons both love it. Great quality and powerful for our hills in our yard!