Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
The people reviewing the batteries are ones who have had to replace their original battery, and generally they're not happy that the original didn't last longer. That's about it...they're decent batteries though. NewerTech makes good extra-capacity laptop batteries, but I don't think they've come out with ones for the MB and MBP yet.
 
so as of now - there aren't any other options...

if one comes out somewhere down the line... is that breaking warrantee?
 
Ah yes, FastMac also has a good line of batteries. It shouldn't affect your warranty, as long as the battery doesn't cause any issues. And they shouldn't...both FastMac and NewerTech are solid companies, so I'd trust their products.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.