Just did the hike two weeks ago with the wifey. (Second time)
I Hiked down Kiabab (yes, I did the Kiabab shuffle), spent two nights at Phantom Ranch in the dorms, and hiked out Bright Angel.
Weather at the top is damn cold (this time of year)
Weather at the bottom was identical to Tucson
Kiabab is steeper and shorter
Bright Angel is longer and shallower, however you spend two miles hiking along the river not gaining any elevation.
Phantom Ranch to Indian Gardens is a snap. Indian Gardens to the top sucks.
The way in hurts (the next day too). Lighter packs really reduce this pain.
They way out is exhausting but not painful.
When you get to the top, realize that you might be dodging cars immediately.
As you get to the top, realize the better people smell, the worse they act.
Eat your meals at Phantom Ranch if possible.
Eat the early breakfast on your last morning at the bottom. It allows for an early start.
Get sack lunches if possible too.
The Stew is better than the Steak at Phantom Ranch.
Take cash, it works everywhere.
When climbing out remember that the air gets thinner and you are getting more and more tired as you get higher. Do not be afraid to rest every quarter mile during the last 1 to 2 miles out.
And, a biggie size Wendy's double burger, fries, Dr. Pepper and frostie 10 minutes out of the Grand Canyon really REALLY hit the spot.