help me decide between dual 2 ohm or dual 4

ok so i have a hifonics brutus putting out 900rms @ 2 ohms running to my pioneer champ pro 12 thats 4 ohm dvc so i also have the same sub but it dual 2 ohm. so if i ran the dual 2 ohm i can run the amp at 1 ohm which its stable at. my question is will this make it sound worse in any way? idk whats better running at 2 ohm or one ohm. at 2 ohms this amp doesnt even get warm. im wondering what the positive and negative will be putting in the same sub in the dual 2 ohm version?