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I would like to have one passive holder for the 3GS of my girlfriend and the iPhone4 of myself. Does someone have experience with this?

I see adjustable versions for the 3GS and the 4 but I don't know which one to get?

The 3G(s) holder from proclip works with both the 4 and the 3GS. The 4 is slightly loose in there but it's not bad.
 
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