Well, it's definitely not as quickly manuverable as a modern sport bike, but it's not meant to be that. It's more of a cruiser with the fat tire up front. I've just put on a new front tire, the one in the picture is an old worn out, flat centered rear, and it still went around corners fine....kind of suprising. Haven't been out on it with the new front yet, but guessing it will roll in to the corners much better.
I've had no issues with the width of the front tire. Like platkeyboy said, tires expand in diameter at speed, they don't get wider.