I too have an M1 MBP and XPS 13. I pretty much always use the XPS. Side by side, there is no noticeable difference in speed for my everyday work. The MBP is more efficient for sure, but I get 8+ hours of battery from the XPS which is good enough - and I can run Linux without jumping through hoops.
Edit: Missed the 'z', sorry, possibly explains different experiences.
Edit: Missed the 'z', sorry, possibly explains different experiences.