IMO single bed size bunks at least make the job of making the bed a bit easier and if both are the same no big arguments other than who gets the top. If a space is too small for 2 teind beds it is too small for full bunks IMO

We had a single over double for our boys and it worked well but there were a few spills off the ladder. If they are young, I’d opt for the safest and most convenient access to the upper bunk or a lower style

When I was a little girl, my sister and I desperately wanted bunk beds. My parents said NO. I am now an adult and have two sets of bunks in a resort rental property. I DREAD making them up. I literally have to be IN the upper bunk to make it. I guess I would ask the question....”WHY??????”

We have single over double and it certainly helps to make up the top bed when you can stand on the double to do so. I'd never do two twins unless there truly was no other option.

How much will they squabble over who has the bigger bed? Twin XL will work into their teens if your family runs tall.

I so agree with the pain that is making up the beds in a bunkbed.

However, if they are not pushed into a corner, then that is alleviated somewhat. Or if at least you could pull them away from the wall to make them and then push them back against a wall when they are fully made.

I'd go with two equal sized beds if you can and also look for bunkbeds that can be separated into two separate beds for future usability as well.

The Pottery Barn one can be detached and used separately. If you can get double over double with that one, it would be my choice although I agree that the other one from RH is more appealing visually appealing. It looks to me like you're stuck with bunks on that one always. So while the kids are small, it works, but as they grown and circumstances change, it may not still be useful.

This is our basement bunkhouse at a rental cabin I manage. Except for the double/single one, they're perp to the walls. If we had room I'd also put that one perp to the wall. You may not have space to do that and you need rails on both sides when you do. You may find it easier to make them up if your fitted sheet and top sheet are sewed together a the bottom so it is a simpler operation. We place two folded flat sheets on each bunk and guests make up the ones they use. We encourage bringing sleeping bags to simply throw on them - kids like that! We keep coverlets on them and shams on the pillows, but don't make them up. Saves time for the housekeeper and guests have not complained. If your boys are going to reach their teens in this space, check on extra long ones and use XL mattresses, which only come in single sizes. I put regular mattresses on these instead of thin bunk mattresses.

A style that converts to regular beds later would be a longer-term, versatile solution.