Judging by reviews, the Framework loses 10% of CPU+GPU performance versus reference designs. That could be due to their memory subsystem or thermal design, or both. Ars Technica said the battery life was "mediocre" but I would have gone with "terrible". Compared to the Dell XPS 13 the Framework has only 60% the life.
As arstechnica noted, the XPS 13 is not a great comparison point because the display is darker and has a lower resolution.