"Better" for what?which one is better?
Probably their favorite USB Loader."Better" for what?
You've just made a very vague question.
HDD is way faster than the SD slot for games.Speed-wise, SD card is better for running games. I used Nintendont on both, and SD loads much faster. So unless you're needing to have a Tb of data on it you need to connect for some reason, SD's likely the better option.
My main experience is with Nintendot. I remember when I first installed it, the recommendation was SD. Is USB faster in every regard?HDD is way faster than the SD slot for games.