Griffin's Reveal is likely the best known case to combine a clear back and rubber sides, but there have been competitors with similar designs over the years. The most recent is Spigen SGP, with Ultra Hybrid for iPhone 5 ($27). It takes the edge protection of Tough Armor, and combines it with a see-through back panel. In addition to one piece of screen film, Spigen SGP also includes two inserts with industrial print that can fit between the case and…