I had a Mk4 until recently when it along with my bikes went missing. I liked it so much I decided to get another so I just got the 800 Mk7. The Mk4 was 800 lumens as well and I felt it was plenty but this one just doesn't seem as bright. It is not dim by any estimate but it doesn't have the same impact as the Mk4. I used to be able to shine that all the way down the road and it was still bright enough or reach the back of the garden with it. Not so any more. Has anyone else compared the two?