Couple of points ...
WizofOz is referring to a 767 as far as takeoff flap is concerned.
V2 varies with factors such as need for tailscrape avoidance, angle of bank requirement after takeoff etc - for example the departure from Cairns rwy 15 required an addition to V2 to allow extra bank angle.
The only time it might come into some sort of relevance is in a go-around situation, where at Vref+5 you can retract to F20 (with restricted bank angle) ...