to me, color is what important. Im waiting for the Red DSi so if the 4" has red and the current one is not yet in the US, I'll buy another one. but, i think, the 4" will drain the battery even more unless it has a 1000 mAh battery or more
Its really your choice. We can't decide for you. Just think about it they are both the same thing except one has a bigger screen and better battery life. I would choose the LL just because its bigger and better battery life. If I ever have to go somewere and I can't put my LL in my pocket I will just take my DS lite. At least its smaller than the PSP.
As far as I remember. Yes. I recall someone having his dsi not turning on as it only went to a white screen every time he turned it on. It was covered by Ninty's warrenty which I believe is a year. How likely is this close to 0%
Of course my memory might be wrong.