If I was to buy one for my car again then iI would be loba every time. Currently running an APR with no issues. After fitting loads of loba pumps I believe they only just out perform the APR in terms of pressure response, build and hold.
Autotech pumps for me are a no go. Can blow seals although it's never happened to me. Very slow at pressure build too. They don't hold consistent pressure either.
Had a bad experience with KMD so will never use them again. They all seized.
Both the loba and apr can support over 150 bar of pressure too.
Off topic a bit, but I've had some info showing that S3 injectors flow more upto 7.5k than rs4 injectors and S3 injectors spray correctly.