The 3 cameras you listed provide almost identical specifications.
I don't know of any professional reviewers that reviews Vivitar cameras. Therefore it is difficult to get comparison data.
However Vivitar did have a group of photos from the 3715 on their website. No photos for the 3705, but I suspect they will be identical to the 3715.
I also checked the Kodak CX7300 photos included in this review:
http://www.steves-digicams.com/2004_reviews/cx7300.html
The Kodak produces a much sharper photo.
The Vivitar photos were "soft".
Based on the CX7300 review and the sample photos, I would select the Kodak camera.
All three cameras use Alkaline batteries which means you will want to get a set of NiMH rechargable batteries (with a charger). You can find these for as low as $10 at Walmart. It will save you money in the long run and the NiMH batteries hold a charge much longer that an alkaline battery.
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I'm trying to buy a digital camera & got so confused..someone suggested for me to come here..Wow!I can't believe I've missed this place. It looks great for me to learn all kinds of "stuff". Ok back to my problem..I don't have much money to spend {$150 or less} need a digital camera that's easy to use. These are the ones that I've chosen so far. Vivitar vivicam 3715 & 3705 and also Kodak CX7300 Any thoughts on them?? Or if someone wants to suggest a camera for me ..that's great too. Thanks

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