I started out with phosban.I was happy with the results but not happy with the media.I don't like that fact that its granular.Reminds me of coffee grinds.To messy for me.I have since switched over to Phosguard.The media looks like small white pellets. Every phosphate reading is 0ppm.I happy with the results and definately less messy.
Be warned that Phosguard is made from aluminum. Many people, including myself have seen certain species of coral (a leather in my case) react very negatively to aluminum based phosphate remover. I will only use iron based phosphate removers (GFO). In terms of pricing and effectiveness I like PhoSar from Warner Marine.