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So, my plan is...

Buy the iPhone 4 (32 GB) for $500 (yes, that's the exact price). Than I'll say to the insurrance company my iPhone 3GS is malfunctioning. Battery empty very quickly, or camera doesn't work sometimes, or touchscreen sometimes doesn't work. Something like that: something which is hard to check ("sometimes"). So I get a replacement (or at least refurb) which is as good as new. Than I'll sell that one for $550.
Disappointed to see this is part of your plan.

Why go the dishonest route?
 
Younwont notice much change from the 3GS to the i4. Display is a bit sharper as is the camera. That's it.. You will be lucky if u don't have any problems like I do with the prox sensor and reception.
 
Disappointed to see this is part of your plan.

Why go the dishonest route?
It's not completely dishonest. There's one small problem with the camera, and I'm just going to make it look worse than it is. Nothing wrong with that, and besides that: I can even hand my phone in for a small scratch if I want (which there by the way is, when you look in a certain angle).
 
I was in a similar position, waiting a year for the iPhone 4. Never had an iPhone before. Then the iPad came out, and I realized the reason I wanted the iPhone was for the apps. So I'm kept my old Nokia that makes calls just fine and I can hold it upside down without losing my signal and bought the iPad. No regrets.

If I was in your shoes I'd keep the old iPhone and get the iPad.
 
I have a 3gs and new ipad. Had fully intended getting an iphone4 but having used the ipad for a week, i couldn't be bothered with the iphone except for the camera
 
After much consideration I think I'm just sticking with my 3GS, get a new iPhone 5 (unless I than want another phone :p) in 2011, and now get an iPad. That's a bit cheaper, and I'm certain I'll have both an iPhone and iPad. Yeah! :D

Not 100% sure yet, but enough time to think about it: iPhone 4 launches here on the 4th of July. Not sure about iPad: rumors say iPad will launch 23 July...
 
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