I recently left a double bed and now have a queen size bed. Even though the difference in size between the double and the queen size bed is only 6", it is quite noticeable that there is more mattress room with the queen.
I do not like king size beds and would never buy one for myself or have a king size bed in my bedroom. Why? In my opinion, king size beds are way too large to use comfortably. For one thing, in order to get into bed and reach your spouse, you have to go through a sea of blankets to get there. Then, in the middle of the night, getting out of a king bed is such a chore and takes so much energy that by the time you pee and make your way back into the bed, you are wide awake from all that exercise. Not to mention that the sheets and bedding require a huge machine at the laundry mat to get that bedding clean and dried. King size beds have not only zip codes, but area codes as well...because they are so large!!