well.. i guess i'll put my two cents in since ive had both..
hands down, my b6 did handle better. the b6 is very tossable and forgiving. the reason i got the 12 is the motor, you cant replace the raw brute pull that big old 1200 mill has. the 1200 likes to walk the back end around if your not careful with the throttle. the 12 take more effort to get it to turn in due to the increased weight and larger tires. they both have their advantages but i do like my 12. I like to ride long distances and go two up any chance I can get (never turn down a ride to a cute girl) and the 12 makes EASY work of the extra weight.