Does anyone have a suggestion on a good replacement battery for a late 2010 13" MacBook air with the core 2 duo? My current battery last 45min to 1.5hours depending on what you are doing. I have read that some of the replacements work well for a month or two and you are back in the same boat. Any recommendations on one that will perform like the original? Ideally I need to get another couple years out of this laptop.