No but it sounds great. I have done lots of holidays there - esp the west coast. I love the national parks. But this was pre-kids mostly. Would depend on how yours are with a) Being in the car for a long time (speed limit is lower so takes longer to get everywhere!) b) Outdoors stuff c) Oooh and aahing over scenery.
You could go to San Francisco and hire an RV for a week or so to go to place like Yosemite and then go to a few theme parks?
I haven't done it in an RV but I've driven across the US a couple of times with the kids and dh in an SUV and stayed in dicey motels. Great fun! Kansas is hell. Try and avoid it. Sooo so dull. Tennessee is scary but worth it for Memphis, Graceland and the Jack Daniels factory (and some gorgeous scenery). Las Vegas is fab. Oh.. it's just good to get out on the road here and drive a long way and watch the scenery change. Texas is good. I love roadtrips for the random stuff - we stopped at a village in Texas and had the best burgers ever at a random church fair... and saw a spectacular (terrifying) thunderstorm in Arizona.
Never had a problem with the kids either if they're armed with --Nintendo DS-- educational books and such.
In fact I saw a great t-shirt that said something like, 'We drove across Kansas.. on day 1 we saw (picture of corn)... on day 2 we saw (picture of corn)... on day 3 we saw (picture of corn and scraggy cow). Next time we're flying'
If you're doing the northeast, that's good too - there's Atlantic City, Toronto, New York, Boston, Vermont... lovely circuit
You've just triggered the very bad memories I have of our RV trip last summer in Florida which I've been trying to block out.
We had a crazy idea of doing a few months around Oz and looked at the Florida one as a trial run. We hired the smallest RV they do which I think was 25ft. It had a small double bed above the drivers cabin, a large single in the main cabin where the table is and you have to convert it every night and a very poor excuse of a double in the back.
There was myself, DH (both on the large side!) DS1 who was 15, DD1 12 and DD2 who was 20 months. DS2 was still cooking and I had horrendous morning sickness.
We drove from our lovely comfortable villa with an en-suite bathroom down to Miami stopping a few times on the way down. Then to the Florida Keys, spending a few days at different places until we got to Key West which was nice. Back up to Miami then across the Everglades to Naples and a couple of days going up the coast before buggering off home to our lovely comfortable villa.
I don't want to put you off but it really wasn't for us. Maybe if I hadn't been pregnant and we'd had a bigger van (or left a few kids at home) and hadn't been eaten alive by sodding mozzies and other nasties in the keys it would have been more enjoyable.
If you are doing it, make sure you have a big enough van and get one that you tow as we found having the 'all in one' very restrictive, particularly in the Keys where we couldn't fit down some streets. Also, our van used to rock all the time whenever one of the brats/little darlings got up in the night so go for one that has some sort of stabilizer thingy (don't know the technical term) that some of the bigger vans have.