Upvote:4
Based on my experience of Ecuadorian electrics, I would assume that even grounded sockets might not be grounded. On that basis, you might as well take an ungrounded adaptor. If you're going off the beaten track, it may also be worth taking a couple of light switches, a small screwdriver, and some rubber gloves.
Since you want to travel light, your best option might be to buy a plug from the US over the Internet and rewire a splitter.