My family was seeking a GameCube for my brother's birthday/Christmas whatnot, and accidentally (sort of) bought a JPN-USA modded GameCube from lik-sang.com. It was a JPN GameCube modified to play USA games, including the appropriate red-white-yellow A/V cord and a stepdown converter. However, when it arrived, it had no stepdown converter, and the manual specifically says not to run it on 120V house current. It turns out it works all right, as lik-sang emailed us, though I wouldn't run it regularly on 120V current because I'm paranoid (and its warranty is only good in Hong Kong).
But it didn't really matter, since it also turns out it won't play USA games after all. (Lik-sang's page says,
Modified with a switch to play Japanese and USA games, but it may mean
modifiable--we didn't bother to see, and there weren't any obvious English instructions to do so.) Parent rushed off to catch Electronics Boutique at the local mall before they closed since they had one and held it (precipitating some familial unrest, but that's all OK now), and they'll be returning the JPN one or selling it on eBay or something.
Ergo: don't buy a gift unless you fully understand everything about what you're buying.