Big block water pumps

2-3 years ago i bought the aluminum 440 source water pump for my 440 and just now ready to install it. IF i remember right, i believe i read (after i bought it) that this water pump does not flow worth a darn..? Its got the 6 curved blades..anyone had problems with it where a regular stock 6 or 8 blade impeller worked better? Its brand new and hate to not use it but if they arent worth a crap, i will buy another pump.wp3.jpg