I have two boys 9 and 3. Oldest co-slept with us until his brother was born so until 6yo, even now sometimes he wants to come back to our bed.
The youngest we put in the same room as our oldest after about a year, he rarely wants to sleep with us.
When they were co-sleeping with us, they would still wake up and cry at night from things other then hunger. Including, I rolled over into my parent and it surprised me so I woke up and now I can't sleep.
In the case of my oldest, he started getting to the point where he would only fall asleep if my wife was next to him with her arm under his head like a pillow. It had to be her arm, we once switched so my arm was under his head and he could tell, got upset about it XD. That is when we decided he needed to start sleeping on his own...which took some time. It is also why we choose to have the youngest move out quicker, we didn't want to have the same protracted experience.
Now they will sleep together at the oldest insistence, about a third of the time though the youngest will take too long to fall asleep and they end up fighting and the youngest will go off to sleep on his own.
I don't think any of us in this conversation have any good data on what is best, and those of us that are parents have way to much bias and way too small sample size to discuss this with any degree of confidence.
My personal option is that either way is not going to make much of a difference and you should do what ever works best for you and your family.
Edit: Added a paragraph(#4)