There's an up side and a down side for each choice. For the BW, the up side is that if you don't like it, at least it won't last that long. The down side is that if you do like it, it won't last that long.
For the YB, it's the opposite. If you like it, you'll still like it three years and 800 games from now. If you don't, you can send it to me and I'll put 800 games on it.
The YB is the best ball I've ever thrown. I absolutely love mine. Hooks on anything. I had to polish it up with the Legends polish to make it usable at my house. For a high-load ball with a (roughly) 4.5 x 3 layout, it has remarkable recovery from inside.
If you have two BWs already, whether you like them or not, it is more than worth it to pick up a YB. It'll be different and I can hardly imagine being anything less than completely satisfied with it. Nothing compares to a high-load particle ball on real heavy oil.
SH