Handsomely designed, Ballistic's SG Series Case for iPhone 4 ($30) is a two-piece protector with three total layers of coverage: the inside is a soft rubber with thick corners that jut out of the second piece, a hard plastic frame with a semi-hard layer of rubber permanently mounted on most of its back. Most of the interesting design touches are on that back surface, which includes the dot-textured rubber, a camera protector with a divider between…
