I have tested in combination 11-50T and 32T chainring for 500 km on hilly muddy terrain and my conclusions are: 
· The cage is to long for a 26 inch bike even with 2.4 tire, and it is very close to the ground and it gets muddy very easily. 
· When the tension pulley become dirtier and it happens very often, the drive train becomes very noisily. 
· The positioning of the two pulley with an angle between their axes create a high wear of the pulleys and a noisily drive train. 
Assuming that the longer Shark cage is necessary to achieve the shifting performance for 
Shimano rear derailleurs. It is longer than a medium cage derailleur, but not as long as a long cage 
Shimano. 
I have changed the the shifter AND the rear derailleur with 
SRAM GX, which has a shorter cage (aprox. 20mm) and it works very good with 50T sprocket. It is a lot quiet, more safe from mud and because the pulleys are larger in diameter the wear is reduced. 
I hope to see sooner available on the site the Shark Kit without the cage for the people that use 
SRAM 1x drivetrains with 
Shimano casette.