Technologically, outboard bearing / splined BBs are superior to square taper, just as threadless stems are superior to threaded / quill, but far more important is the quality of the parts. There are plenty of very powerful keirin racers that do just fine on square taper / quill setups. Over/under tightening of a square taper BB won't occur if you use a decent quality torque wrench.
__________________
What, Me Worry? - Alfred E. Neuman
I'd like to think i have as much money as brains.
I see the light at the end of the tunnel, but the tunnel keeps getting longer - me