Digital BW, The Print

I'm having the darnest time getting a comprehensive comparison of the
Nikon LS5000 and the Minolta 5400 compared to my Canon FS4000.  I know
the newer scanners have lots of new features, faster scanning, better
bit depth, ICE x 4, etc.

What I want to know is, do either of these scanners work better with
B&W negatives, OR pull better shadow detail with slides, than the Canon.

I already have the Canon and can live with its limitations.  But I'd
consider upgrading if the image quality were noticeably better.

All comments w/b appreciated!  Thanks!

Robert Ades