If you have the time, desire, a travelling buddy, and a little spending money Id put a vote in for the drive/adventure.
Ive driven across the US twice (once all the way to Alaska), logged thousands of miles in a number of the western states, and have covered half of Australia via road trips and enjoyed mostly all of it. Some of my best memories in fact. Take a camera (I guess a smart phone works now a days) and plan your route, stops, and sights of interest along the way ahead of time -- you will never forget the experience.
. . . I will admit that my travels did not take place in a FJ40 and my speed/comfort was probably a couple notches up. I also planned my travels around the time of year/weather -- I would not want to drive thru the mountains this time of year and snow can be up in the higher elevations well into June. Just an opinion. . . I am at a point in life where I could not take on such an adventure with a wife, mortgage, and business to run. . . but I am glad I did when I had the chance.