
Exped
MegaMat Series
Car camping comfort champ, but some side sleepers find it thin.
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REI or Nemo (or exped, but imo either get the REI for less or the Nemo if packed size is important to you). I’m talking about their self inflating foam and air mattress in the two person size. And get a backpacking quilt from feathered friends.
This is the answer! I have a double REI Dreamer matt, but after complaints from my wife (I weigh 40 pounds more) about sleeping on a brick, I bought two individual matts. Much more comfortable as each of us can adjust the firmness and not feel each others movements
Hybrid foam/air pads like Exped mega mat or REI camp dreamer are the most comfortable and packable for couples IMO. I’m sure there are other brands too that are similar. Problem with air mattresses is it feels like a waterbed if one person tosses. Cots are big and bulky and I don’t know of any 2 person versions.
At 50, only pad I find comfortable is an REI Dream mattress. I've done way more car camping than before since getting it. That said, I don't hate my Neotherm but I have learned I can not sleep on my side when using it or any other thin pad. I must sleep on my back and tummy. Might jusy need to change your sleeping habits.
REI makes their own knock off of those mats. I have two and have had them for about five years with no problems. They’re called the Camp Dreamer.
For car camping (which we generally always do in mild summer weather), my wife and I use a double size REI Camp Dreamer (comparable to the megamat) and we zip together regular old Coleman rectangular sleeping bags that I got at Costco. When backpacking, we use completely different gear.

Exped
MegaMat Series
Car camping comfort champ, but some side sleepers find it thin.

Exped
Ultra Series
Lightweight side-sleeper comfort, but a bit pricey and bulky.

NEMO
Tensor Series
Ultralight side-sleeper comfort, but slippery and prone to leaks.

Big Agnes
Rapide SL Insulated Sleeping Pad
Comfortable with side rails, but heavy and warmth claims disputed.

Therm-a-Rest
NeoLoft™ Sleeping Pad
Very comfortable, good service, but heavy and bulky for backpacking.

Ranked #1
Exped - MegaMat Series

Ranked #1
Exped - MegaMat Series

Ranked #1
Exped - MegaMat Series

Ranked #1
Exped - MegaMat Series

Ranked #1
Therm-a-Rest - NeoAir Xtherm Series