My experience with OB speakers is that the hype surrounding them in recent years is mostly unwarranted. They do sound different from most box speakers but not necessarily better. Of course if you spend $10K on a well designed OB speaker, it’s likely going to outperform a $5K box speaker. I suspect that many listeners who made the move to Spatial or Pure Audio Project OBs and raved about the performance were upgrading from cheaper box speakers.
Personally, despite their considerable shortcomings, I prefer Magnepans and ESLs to any of the dynamic-driver OBs I’ve encountered.
One trait that has been consistent among all dynamic-driver OBs I’ve owned or auditioned is substandard imaging, probably due to the requisite width of the baffles. Also, none managed to completely do away with the resonances typically associated with box speakers the same way a panel speaker can.