I have a few different filters that use these filter cartridges,and I am pretty pleased with the results.
You can pull the cartridges out when you see that they're getting very dirty,and just rinsing them in a bit of old tank water,revives them and gives them a longer life.

Pros: easy to find hold up pretty good

Cons: none

My little 10 gallon set up uses these filters. they couldn't be easier. I just wish they weren't so expensive when you need to replace every few weeks.

Pros: Ease of use

Cons: Price

I have these on one of my filters. They are easy to pull put and replace though you have to be ready for the dripping water.

Pros: easy to use

Cons: none