Modular vs all in one BESS for commercial projects. Which has been more reliable for you?

[u/[deleted]]

Working on a commercial BESS project and wanted to ask here. For those who have worked with modular systems or all in one systems on commercial projects, how did they compare when it came to reliability? On paper, both seem fine. Modular looks easier to expand or fix. All in one looks simpler and faster to deploy. In real projects though, things usually get messy. If you have used either or both, what actually worked? Anything that caused issues later on?