I have driven cross country twice, in both cases they were B bodies. Both of those threads are on FBBO if you care to search for them. We posted pictures as we travelled.
First time was in 2015 in my 1970 Air Grabber Road Runner. That time I drove it one way and had it shipped back. The second time was this year, May and June of 2022. That time I drove my 1973 Road Runner and we drove all the way to the Pacific, then all the way back (11,097 miles). Both cars are pictured below (and in the same condition/ options they were driven in).
The 70 is a fully restored, no expense spared car. I will have to say that it was a bit more comfortable because it had no rattles, squeaks, etc. The 73 is a bit of a beater, with some rust and issues. The 70 is a 383 manual while the 73 is a 416 (stroked 340) automatic.
Really, both cars were comfortable to drive in. The suspensions on B bodies really work quite well, and I think they are the perfect size. Not too big to fit in smaller parking spaces or tight spots, but big enough to be comfortable in.
Some suggestions if you are considering this:
* Make SURE your suspension is in GREAT shape. Many cars of this vintage have sloppy, crappy suspensions that wander and drive poorly. We hot rodders tend to focus on the engine and driveline, but the suspension is a key part to making the car drive nicely.
* I feel that overdrive is a must have. The 70 had an A833 built into an overdrive (now it has a A855 Passon overdrive), and the 73 has a Gear Vendors overdrive. Both of these things make cruising the highways way more tolerable for long periods.
* Have a reasonably quiet exhaust. Again, most of us hot rodders love a loud, race car kind of sound. But that gets old quickly when you are driving every day for hours in the car.
* Have air conditioning. My 70 does and we loved it. My 73 does too, but it failed about a week and a half into our trip. Driving through the desert with a black vinyl interior sucked.
* An engine that runs on 87 octane (or less) is a benefit. My 73 runs on 87 octane, and this saved us a bunch on money. It still has power galore too, so a fun combination. Not too radical, but not tame either.
Feel free to send me a PM or ask further questions here - happy to help with further thoughts from my drives.