It will help if you indicate what type of vehicle you're taking and how much room you'll have.
I've used all sorts of ground tents over the years, from simple tarps to big two-room tents and have to say,
having a hardshell RTT is SO much easier and more convenient.
Level up the vehicle and pop up the tent. Super easy up and down, leaving you more time to enjoy yourselves at whatever places you stop. Easier in the dark, too. Easier on uneven or rocky ground. Don't have to unpack/pack it in a vehicle full of three people's gear and clothing.
One disadvantage to a RTT, if you have it on your vehicle and not a trailer, is that you'll have to pack it up if you're going away from a camp site for the day. Not as big a deal with a hardshell as it is with a soft fold-out RTT.
There are a mess of hardshell RTT companies now, from
Maggiolina/Autohome (the original rooftop tent, started in 1958 in Italy) to Roofnest to James Baroud to Bundutec and more.
I bought mine used for about half price. I would check the adventure forum For Sale sections and craigslist for cities all around you or close on the route you're going to take.
Let me know if I can answer any specific questions about installation, ease-of-use, maintenance, etc.
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Roaddude - Traveling Photographer/Writer/Artist On the Road In North America. Gear, reviews, people, places, and culture.
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