Craigslist

I got a new (used) tank off of craigslist today and went to pick it up. It's a 44 gallon petagon with "oak" stand. It's in decent shape, there's some inside scratches on it. The guy gave me some gravel, an undergravel (blah), air pump, and fake plants for 120. I also got this filter, it's called a "Millennium 3000." I've never heard of it- how good of a filter is it? Right now I'm guessing it...