I get the sense that he thinks the RV will be cheaper than hotels--not that they are to be "avoided" because of some reason.

I'm with Utahtea having done a heap of RViing. What is missing in these posts are the various RVs that can be rented. Start with Class A (Grayhoud bus size) Class C (Cab over - most popular) to economic Class B

Cruise America is one of the larger:
http://www.cruiseamerica.com/
And many others

Or from private individuals
http://privatemotorhomerental.com/

Look at their Class B option. Quote:
Daily Rental: $50 Winter ($105 May1-Sept30 Summer) ($150 5/23-29 & 8/27 - 9/5 Holiday)

Camp sites are from $30 plus for full service; less if dry.
Insurance, damage, etc. - the fine print stuff.

Bottom line: Don't have to hunt for bed bugs every night and there is always a cold beer/wine & sandwich.

Bed bug registry:
http://bedbugregistry.com/

Vaga.

I agree with the others. If this is your honeymoon, I'd make the drive in a car and/or fly out west and rest a car there. You have four days of driving before you get to your destination and four days back. Not to insult anyone in the middle, but it's not exciting driving. You'll make better time and spend less money if you drive and stay in hotels and that gives you the flexibility to mix things up re your hotel choices.

If you want some ideas on how to break up the drive, tell us more about your interests and if you want to have a driving day of 8 hours or 10 hours. One random suggestion on breaking up the drive -
Segment 1 - drive to Amish country. Bird-in-hand, PA would be 410 mile drive or just under 7 hours.
Segment 2 - drive to the Ohiopyle, PA area if visiting Frank Lloyd Wright's homes at Fallingwater and Kentuck Knob would be of interest. That would be 207 miles and 3.5 hours. You'd need to add in a day or two to explore the Amish countryside and have time to visit the homes.
Segment 3 - drive to Springfield, IL or St. Louis, MO = about 9 hours of driving. Add in time to visit Lincoln sites or go up in the Gateway Arch
Segment 4 - drive to Hays, Kansas - about an 8 hour drive day
Segment 5 - a short drive day that will get you into Colorado
Segment 6 - spend a few days exploring Colorado
Segment 7 - spend a few days exploring Bryce and the SW desert
Segment 8 - start heading back, maybe stopping at Mammoth Cave and Washington, DC.

It's hard to know what to recommend, but use google maps to play around with the routing. No matter where you stop along the way, your going to have a 5000 mile/ 8 days of driving to get there and back. "The middle" isn't very exciting driving and/or particularly interesting RV camping destinations. If you drive it, use a car. If you want the RV experience, fly out there and rent an RV out west. 5000 miles in an RV in just travel time is not a very exotic honeymoon. It's a pretty tedious driving vacation.

I agree with all of starrs last paragraph. Since you want to see Zion/Bryce, fly to SLC and then drive a rented RV from there.
You don't really want to drive an RV through Chicago and across Nebraska or Kansas.

>>Since you want to see Zion/Bryce, fly to SLC and then drive a rented RV from there.<<

I'd think flying into Las Vegas makes a lot more sense. It 150 miles closer to Zion/Bryce and there are better flight connections from almost anywhere in the country.

Just one piece of advice in addition to all the suggestions above: triple check the height of your RV against the allowable vehicle height of any bridges, etc you have to go under or over, esp on back roads. On lots of non-highway roads, you can find some mighty low bridges (the part of Pennsylvania I grew up in is full of them). You do NOT want to get stuck or damage either your RV or the bridge!

If you are interested in history, I recommend stopping at Presidential libraries. We've been to most of them. Our favorites are Ike and Truman. Least interesting is Prez Ford in Michigan. Also birth places of Presidents. Tyler was very austere.
While not a classic prez library, Lincoln's is also recommended: There are many, but this is the one we visited:
http://www.lincolnlibraryandmuseum.com/lincoln-tour.htm

Next, have a tour of each State's Capitol. Texas is impressive in design and history. Texas had the following flags flown: Spain, France, Mexico, Republic of Texas, Southern Confederacy, and the United States.

Wyoming's tile is beautiful (imported from Alaska)

Vaga