See other thread:
Battery Life
Battery life depends on many factors, outside of "quality". If you are going to let the car sit, use a Battery Tender.
I drive my car once every 2 weeks and sits in the garage the other times. I use the Battery Tender once a month, and she cranks up just fine.
Personally, I use Duralast Gold and replace my battery every 5 years. Use the battery felt rings and terminal grease each swap.