Hi,
KSB are a German based pump manufacturer with branches throughout the world, they have been around awhile, not sure exactly when but certainly before 1900, yep you read right 1900. They are known for producing v/good submersible sewage / effluent pumps. I you do a google you may be surprised, would i use them yes, after evaluation of application & competitor options. But if everything looked ok then i wouldn't hesitate to use them. Just in case anyone may think I am associated to them i am not, Just worked with sewage / effluent pumping stations for- 40 years in Europe etc etc.