Need tire advice: drag radials

How important do you think that 1/2" is past my 7"? Have you ever had any problems with them? Do you inflate them differently on the street vs. at the strip?

And... what do you guys do for the front wheels - do they get drag radials too?
(Sorry about all the newbie questions. I'm a total newbie!)

You always want a matched set. Radial back = radial front, bias back = bias front

That 1/2" doesn't make a **** bit of difference.