I have had as the pneumatic system than hydraulic system also as flowserve system than ruhrpumpen system as much the hydraulic system as the pneumatic system operates well, In the case of the rotary joint I have had both systems( Ruhrpumpen and Flowserve) The ruhrpumpen systems is more robust and strong that flowserve, since it has less mechanical pieces internally (bearing). this rotary have only one gear connected to the pinion of the motor (hydraulic) for that reason is less propitious to faults, in fact all the system is more robust (including free fall arrestor) from the mechanical point of view the cutting tool has a system of change mechanical (initial to final cut) through a lateral nut (you dont have to take out the tool totally to make the change)
bets regards