I agree with @gigigigi
I think sleeping in the same bed is cute and cosy when you're boyfriend and girlfriend, and in the early throes of your relationship. (And you are only sleeping together all night once a week when staying over at each other's place/your parents place.)
But sleeping together in the same bed, long-term, every night, is, IMO, just simply not doable, not conducive to a good marriage, and not good for your mental and physical health.
I am sure some people will dispute that, but based on my own experiences, and that of many people I know, separate beds, (even separate ROOMS) is the way to go. It makes for a better sleep, better rest, a better relationship, and a better marriage.
Some people have suggested 'super-king- beds, but that doesn't eliminate his snoring, and coughing, and throat-clearing, and grunting, and getting up and down to the loo, and duvet hogging..... Separate bedrooms is the answer to a great sleep, and a happy marriage!
I also wonder; why a 'super-king' bed? Why not separate beds? 
The OP is correct; when you are in the same bed, you simply can't have a decent night's sleep. You get too hot, he snores, he grunts, he pulls the quilt off you, he kicks you, he coughs, he punches you, he elbows you, he clears his throat, he sneezes, he gets up and down t the loo, he hiccups, and fuck knows what else.
I lost count of the amount of times DH pulled the duvet off me, elbowed me in the face, ribs, and back, coughed loudly in my ear (just as I was dropping off to sleep,) and started snoring loudly when I had just dropped off into a peaceful sleep. It was literally like some kind of P.O.W. camp torture.
I regularly felt lethargic and fatigued, and had to go to work on it. 3 years I tolerated it (in our 1 bed flat,) and regularly crawled onto the couch to get a much needed 5 hours straight-through sleep.
When we moved into a new 2 bed home, I had some relief as I slept in the spare room sometimes, but our daughter came along after 2 years, and I was back to square one - sleeping with him and struggling again.
So when she was 2, we decided to move her into a bed, and we got bunk beds, so I could have somewhere to crawl into when he kept me awake. (He couldn't go in the bunks, as he is 5 ft 10 and was 15 stone,) and the beds were for kids (up to about 12.) Because I was 10 stone and 5 ft 4, I was able to fit OK in the bed.
Then we moved to a 3 bed home (nearly 15-16 years ago,) and I got a bedroom of my own, made it my own, and never looked back. I could never ever share a bed OR bedroom again with my DH. Or any other man. If we split or he died, and I entered into another relationship (which is very unlikely,) I would never share a bedroom, never.......
We have a perfectly, decent, happy marriage and a decent love life, but do not share a bed. Some men are pretty arsey about having separate bedrooms as they see it as a slur on their manhood, but my DH doesn't mind. I think he enjoys the peace too.
As the OP said, I cannot fathom how anyone can share a bed long-term, and think it's quite unnatural to share as you simply cannot sleep for any good length of time. I think it all harks back to the days when people shared a bed to keep warm, and eventually married couples were expected to sleep together.
I used to be embarrassed about it, like we weren't normal, but over the past 10 years, I have heard of so many couples choosing to sleep separately, and some who don't (coz there's no extra bedrooms,) saying they envy me, so I don't feel bad about it now. And I don't care about saying we have separate bedrooms.
Even when we go on holiday, we have separate bedrooms. The last time we went and had separate bedrooms, a few married couples there were really envious, and wished they had done the same. 'I didn't know you could DO that! they said LOL! It obviously costs more, but I would rather pay £900 for the 2 of us for a week abroad with a bedroom each, than pay £700 and have to share a room.
I will never ever ever share a bed OR a bedroom with ANYone again, as long as I live.