the 3DS XL may have a longer battery life, but it's not necessary to get one just for this reason alone. If the screen issue puts you off then you can always get a normal 3DS and fit it with a Nyko Powerpak+ (which more than doubles the battery life) as I have done.

On the other hand 3DS XLs are less bulky and clumsy-looking, plus there is a pikachu version which looks AWESOME. If I didn't already have my 3DS before the XLs were released, I would have gone for an XL, personally.