I am yet to decide which bio media is the best I am pretty sure even the cheaper stuff would hold tons of bacteria.. It is a difficult one because the bacteria will only build up to a level to suit the bio load in the tank, you cannot see either of these things so how much do you need? You could spend tons of money filling this with the eheim stuff and not need it but never know.
I know that I have used the cheaper ceramic rings, pumice, terracotta beads (that you get for putting in pot plants) even just used filters with filter wool in big tanks and had no issues I think I have some of that eheim stuff mixed in with all the others too.