Well after much debate with myself and reviewing every case out there that works with iPhone 3G / 3GS I opted to go with the InCase Slider! Only problem if you have a full body Invisible Shield it is a nightmare to get on and off which defeats the purpose. So, I sent email to Zagg and they told me just to take the front and back off, send it to them, they will refund my money, then I can just get the front screen protector only.
I love this InCase Slider, because it really doesn't add a lot of weight or bulk, yet seem to provide really good protection with a matte finish (no fingerprints). I went on and picked up another Invisible Shield front screen only at Best Buy, so now Zagg can just refund me the other one. Anyway what I like most about this InCase Slider is that you can just simply slide the bottom off and dock it in just about any dock, so that means I can use it my JBL On Stage or 3G standard dock with no issues. Slides in and out of my pocket without picking up lent. It is recommended that at least once a week you take it out totally give the phone and the case a good wipe down and the put it back together. Sounds reasonable to me! I am happy with it, so if anyone is looking for a decent case that doesn't add bulk to the iPhone 3G or 3GS take a look at this one. It is available in several colors and ranges in price from $29 to $35 depending on where purchased.
Slider Case for iPhone 3GS and iPhone 3G : Incase Product
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iPhone 4 32GB, Black,
iPad 32GB 3G/WiFi
MacBook Pro 2.27GHz, nVidia 256GB, 4GB Ram, 320 GB HD
Mac Mini (Home) 2.53GHz 4GB Ram, 500GB HD