Yes, I believe most of us, if not all, prefer low maintenance tanks. I like the co-op sponge filters as well. They worked great when my fish population was smaller. I do recognize that I need to decrease the number of fish in my tanks. I am currently building a fish room where I will add more tanks and distribute the population across multiple tanks. When I had less fish, I didn't feel that I had to service my sponge filters often. Once again, I am not creating a debate on what type of sponge filters are better. I am simply bringing some facts up to all of you, co-op sponge filter users, co-op sponge filter sellers and designers, in case the information I have can be useful to any of you. Feedback is usually what helps people make a better product.
From my experience, having around 150 to 200 xiphophorus helleri in 75 gallon tanks with three large sponges, the filters were not keeping the water quality where it needed to be, even though I cleaned one filter every week. When I replaced the sponge filters with a dense sponge filters, the water quality improved and my fish stayed healthy.
The other difference I noticed is that when I would pick up the co-op sponge filter to take it out of the water, stuff started floating out of it. Yes, I did watch Corey's video on how to properly clean the filter by using a bag to put under the filter as you lift it up. However, in a heavily planted tank that is a bit difficult. The dense sponge filters hold that stuff in much better, but it does take a bit more effort to clean the dense sponges.