Without a doubt, I prefer the higher-pitched voice of Bloo. As others have said, it fits so much better with the character.
Although I have to admit, the scene in which Bloo and Coco are conversing for the first time still makes me laugh, with the lower-pitched Bloo responding so plainly and matter-of-fact like.
Coco:
Coco?
Bloo:
Yes.
Coco:
Coco?
Bloo:
Yes.
Coco:
Coco?
Bloo:
Yes.
That worked for me.
