I've had great success using the 360/720 method of upresing images to 360 or 720 ppi when the native resolution is below those marks. Up until now, I didn't have a camera that had high enough resolution to stray from that. However, now with the D800e, I'm finding when printing smaller prints, I'm well above even the 720ppi native resolution.
Is there a general 'rule of thumb' when this happens? Do you downres to 720, go with the native resolution (900+ for a 5x7) or is there another plateau to res-up to (1440?)?