4" (4.5"?) lips for you. Axis achieves the extra lip width because of the spoke design. They curve inward towards the hubs where most wheel spokes are flat or straight and in front of the hub.
http://www.axiswheels.com/Axis...5.jpg
Quick-A staggered setup will generally mean you wont have the ability to rotate tires front to back. Unless you dont mind or the stagger is small enough where it wont be readily noticed.
As LBC said - definitely buy a wheel guide - this will tell you the recommended specs on upsized wheels for the Altima as well as the G35/Z. I mention the other cars because the specs for these (which are staggered from the factory) - may work for you.
Besides selection and price, the other major factor I would say is - how are you going to do the purchase. I chose a local rimshop - as opposed to mailorder. I wanted to have an extra measure of support.
Nothing beats seeing the wheel in person. Going through a local shop may give you the opportunity to see the wheel (or wheel size) on your car before you purchase.