As simple as its Apple-designed interface may be, YouTube’s unfiltered mish-mash of user-submitted content can make a very poor first impression on Apple TV. Depending on the videos you initially stumble across—their content, not the quality—you may swear that you’ll never try YouTube again. But further testing shows that YouTube on Apple TV is redeemed by better-than-expected H.264 video quality and a search feature that already…