Trying to determine the differences in the 9 & 10 are. I do know the 9 screen resolution is 480x800 while the 10 is greater at 600x1024. Also of course the screen is 1" larger. I was going to buy the 7 SI but decided I need the larger screen. If those are the only differences I am not sure it's worth the extra $500 to purchase the 10? Any thoughts/feedback appreciated.

Thank you!