The cell phone manufacture may not make a difference in the phone but I think the orgin of the cells in the batteries do. As I recall seidio also said that there are cheaper li-on cells made in China while the better quality ones are made in Japan. Although I haven't tried an official test through a static environment, my cell phone battery usually does last longer than my friends. His is a Cingular, mine is a T-mobile so that may be why but my battery is made in Japan while his is made in China.
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Very happy with my BlackBerry Pearl 8100 !
PIN: 23E72DC3
My phone is Laaaah-teee-nooooo (in best Pitbull voice...)
I got it about a month ago... The 611 rep and the T-Mobile store rep both talked it down saying the Dash was better. I think I made the right choice sticking with the Pearl.