I've use several chain cleaning tools, but the Park Tool Cyclone Chain Scrubber does the job best, does not fall apart and the tip on the instructions saves me a ton of money. Once I ran out of citrus cleaner, the tip says to use water diluted Dawn dish soap for chain cleaner fluid. It works great and cleans up easy.
This baby lives up to the hype. I wash my chain every other ride and it only takes 10 minutes with this. I like simple green diluted to 50/50 to scrub my chains
I have used this for a year. Used with proper degreaser it will completely clean your chain to a like new state. I use zep citrus degreaser from a hardware store. The only problem I have with this scrubber is the brush bristles get stuck in the chain. So make sure you pull them out.