I bought the Skyrocket and my wife got the plain Galaxy S II. With no active use, just two email sync services, my battery is down 15% after 4 hours. My wife's phone with similar settings is down 10% after 16 hours. That seems like a pretty large difference for only having to power a little larger screen, little faster processor, and LTE radio. Especially since we're in an area that doesn't have LTE or HSPA+.