Well, having had a hassey and a Bronica....
the biggest difference I found between the two was that the hassey was heavier. Not an advantage in my book. I prefer my Bronica. Solid, very dependable, and you don't have to rent out the children in order to afford lenses and accessories. And the lenses are very, very sharp.
So, I suppose if you have your heart set on a hassey, go for it. But I think Bronica is underrated and is a better use of money.
For what it's worth, almost every image on both of my sites ( www.cheryljacobsphotography.com and www.cheryljacobsportraits.com) was made with a Bronica. There are maybe five or six hassey shots there, and I'm pretty sure you can't pick them out.