Their description:
Product Description
Never before has the flexibility and protection of a soft rubberized case been combined with the durability and scratch protection of a sleek hard shell in a seamless single-piece design… until now. CandyShell’s soft, colorful rubberized interior keeps your iPhone 3G or iPhone 3GS insulated from life’s bumps and knocks, while the shiny outer hard shell protects it from scratches and lets you slip it in and out of pockets easily. Full access to all ports and sensor… More >>
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Speck Products CandyShell Case for iPhone 3G, 3G S

I have had my speck case for my iphone for only one month, and it now cracked along the charger portion. The case also does not come off easily, which likely led to the cracking issue. The gummy rubber of the case attracts lint and does not look good after the first few weeks. I like to plug my iphone into a Bose speaker set at home, and a regular Aux in/out input does not fit with the case on the phone. I have to remove the case to use the Aux in/out connector.
I have try many iPhone 3gs cases, Switcheasy Neo, Switcheasy Rebel, Incase Slider, and this is by far is the best case I used.