There are no power or fuel efficiency increases. They switched them independently, like I already said, for a smooth linear power gain. In other words so you don't notice them engage.
We are tuner car fanboys and want to notice that shit, so quit worrying about switching your cams at different points, go Honda on that shit and switch them both at 5000. Lol oh wait, I might start a bickering war with that one lol. Everyone has different opinions on what you should set your cams to. Some people have dyno proven results on what the best cam activation point is. Dyno results never, to my knowledge, proved to be beneficial for anything other than smooth power.
Iirc Intake switches at 5200 and exhaust at 5600 or 5800 on OEM setup SR20VE cars.