I've bought 2 bouts and am having trouble with getting a nice finish. One is a 2x4 from Superior shave. The other is a belgishire Brocken #5 extra fein approx 1x4. I managed to get a great edge from the Brocken. But I've been going at that one for 2 weeks every day with different razors. The larger I just cannot seem to get a good edge at all. I've tried taking it up to 8k on naniwa ss stones and it just takes the keenness away. The larger also does not like to slurry much and its very very slow. The Brocken slurries and cuts fast.

Am I just not giving it enough time or what?

The first is from superior shave and the second stone is the Brocken. Both have dry, wet, and slurried pics.