If You want to see some pics here we go: (sorry tests in polish)

http://bron.iweb.pl/viewtopic.php?t=23569&highlight=e59

http://bron.iweb.pl/viewtopic.php?t=23550&highlight=e59

My quick conclusion:

pros:

-concentric clamping like BKL
-price (here 10Ł)

cons:

-ugly
-need attention while tightening
-not suitable for FAC springers unless u use red loctite glue