You can't really say one case gets more dusty than others. The Antec 900 has a lot of airflow so naturally, you can expect it to accumulate a lot of dust (if you are in a dusty environment). Other cases with similar airflow, such as the Armor series, gets the same amount of dust.
The only way to eliminate dust with a lot of fans is filters.
The only way to eliminate dust with a lot of fans is filters.