Depends on your personality. I started in a single-man cell for the first few months, then I was in the Hole for a couple of stretches and that was solitary, and then during COVID I got my own cell again for about 8 months. I am an only child, so I am incredibly comfortable being alone for long periods. I hate sharing a cell with someone else, as 99% of the time you probably won't like the other person. Most two-man cells only have enough floor space for one person to stand, so you are constantly shuffling around each other. And bumping into anyone in jail is immediate grounds for a fight, so you are constantly on guard.

Plus, no-one wants to be in the same box as another man who is taking a shit. And the food is so bad that practically everyone has diarrhea all day every day.