I had Spiegler bars on my gen2 Busa, and traded it even for a B-King.
No regrets. I found the B-King alot more comfortable with an upright riding position.
I flashed the ecu as a gen2 Busa, did a ram-air mod(B-king has no factory ram air), removed valve from midpipe.
A 46 tooth(+3) rear sprocket. Completely different bike.
Bar end mirrors were a huge improvement in visibility and looks.
Had 2bros cf mufflers on it when I got it.
Horribly loud, cost $90 for inserts. They made it quiet. I cut them 3" shorter too.
Was going to put a gen2 Busa full single Akropovic on it.
B-King is a great bike.
I sold it after a year and a half.
I'll be buying another gsxr1k and adding Spiegler bars next.