Best Ball Cups available

[chb]

I am wondering which Ball Cups (=Rod Ends, Ball Ends) to get for a b4

After a few searches on this forum, I didn't find a dedicated thread...

However, I found some info and the following cups mentioned:

# RPM
# LOSI
# JConcepts
# Associated #7230(b4 defaults) or #6274
# fastrax
# ... any other?

Main concern is quality such that they are not loose(no friction either) on the ball

Thanks for your opinion