I hunted unit 73 for the first time this year and drove out from the East Coast. I never had to put the truck in 4WD. It was dry the first few days of the hunt, then we had rain, and a bit of snow.
I looked at flying out versus driving from a time and cost perspective. Denver makes a lot more sense than Casper, to me.
My wife, a friend, and I hiked for miles the first few days glassing, and just didn't get up on any at ranges they were comfortable shooting. Meanwhile, two of our three buddies gave up hiking in the first hour or so and cruised the roads until they saw antelope, got out, walked up the ravines until they were close enough and tagged out two and a half hours into day one. I did see a few hunters that would drive, jump out of a rental SUV, walk not quite far enough away from the road to be legal, take shots, miss, and get back in the truck and continue on.
All six of us had doe tags, and I read everything I could find about 73 beforehand and most of it said there were no trophies in 73. I probably don't know the difference in a 12" or 14" buck at distance, but there were some impressive bucks out there.
The toughest part of our trip was housing. Originally, I rented a place through HomeAway.com or VRBO.com months ahead, and the owner sold the house and cancelled on us a week or two out. I found another place through AirBnB.com that I will highly recommend if you're looking up on top of Casper Mountain. We were a bit of a haul from our hunting area, but it wasn't like we had to be out there early...there were no shortage of antelope, no matter the time of day. We even saw a heard of about 25 elk that the locals say is rare out in that area.
Most importantly, if you like breakfast, you owe it to yourself to eat at G-Ma's Diner!