I quite like this case. It sits well in the hand, works against slipping, feels like it protects the phone, has a nice pattern, and yet you can see the steel and other features, which I feel is important. All the access openings are perfect. It exists in a few other colors too.
I tried Apple's bumper case, and I feel it's a failure compared to this case. The Bumper hides the beautiful steel, and it does not protect the back glass.
CS-Styles have wasted no time in promoting that it helps with Apple's little antenna problem too. :-)
I like their Chinese-English promotional text:
"Now the world is crazy by the new release iPhone 4. Come on everyone. Keep your pace on and do the complete prepare for it. DS Lattice Silicone Case is a have-must. The lattice pattern is simple but fashion."